[Updated (4/19/2013, 9:08 p.m.) with word of the arrest of the second suspect.]
Students and faculty and staff members at Boston colleges awoke on Friday to urgent warnings to stay indoors as their campuses closed in the midst of a manhunt for one of the suspects in the Boston Marathon bombings.
After a day of anxiety and tedium as police officers methodically searched a large area of nearby Watertown, Mass., for the suspect, 19-year-old Dzhokhar A. Tsarnaev, he was found hiding in a boat stored in a backyard under a tarp, and taken into custody. The other suspect, his 26-year-old brother Tamerlan, was killed early Friday morning during a shootout with the police.
The daylong drama began late Thursday night, when a campus police officer at the Massachusetts Institute of Technology was killed, shot multiple times as he sat in his patrol car on the campus. It was the first in a series of violent events allegedly involving the suspects in Watertown and Cambridge, Mass., just across the Charles River from Boston.
On Friday morning, students at the University of Massachusetts at Dartmouth were quickly evacuated from their dormitories when the authorities learned that one of the brothers had been living and studying on the campus.
The suspect who was killed, Tamerlan Tsarnaev, had been a part-time student at Bunker Hill Community College, a Boston-area institution, several years ago. His brother, Dzhokhar, escaped on foot and was apprehended by the police on Friday evening after some 16 hours on the run. He was enrolled on the Dartmouth campus and had worked intermittently as a lifeguard at Harvard University.
The manhunt shut down much of Boston on Friday, with some 50 colleges in the area closing for the day. The two bombs that exploded on Monday near the marathon's finish line already had deeply affected many of the colleges, whose students were among those injured. Students and faculty members at Boston University, in particular, have been grappling with shock and grief after learning of the death of Lingzi Lu, a Chinese graduate student in the mathematics and statistics department who had been cheering on runners near the finish line.
'Profound Sorrow' at MIT
At MIT, the officer who was killed was identified on Friday morning as Sean A. Collier, 26, who had worked at the university since last year. He was a resident of Somerville, a city just north of Cambridge.
The shooting, which occurred at about 10:30 p.m. on Thursday, led to tense hours on the campus overnight. The university sent out a text alert and tweets warning students to stay indoors and asking people to stay away from Building 32, the campus's well-known Stata Center, where police officers and SWAT teams were gathering. A message posted on MIT's emergency-information Web page shortly before 2 a.m. said the police had determined that gunmen were no longer on the campus, adding, "It is now safe to resume normal activities. Please remain vigilant in the coming hours."
But shortly after 6 a.m., the university canceled classes for Friday and told employees that they could take excused absences.
The president of MIT, L. Rafael Reif, was returning from a trip overseas on Friday morning. He sent a brief e-mail to students and members of the faculty and staff.
"Writing between flights, eager to get home, I am struggling to grasp the events that have frozen our cities and our campus," Mr. Reif wrote. "I want to express our profound sorrow for the loss of Officer Sean Collier, and our enduring gratitude for his service and his extraordinary sacrifice. To his family, we offer our deepest sympathy.
"We will find ways to console one another at this time," he continued. "We will come together as a community soon. I should be back on campus this evening, at home with you."
Mr. Collier graduated with honors in 2009 from Salem State University, where he majored in criminal justice. He was active in the MIT Outing Club, an outdoor recreational club for people on the campus and alumni. On Friday the club's members quickly created a Tumblr page where they shared photographs and memories of their lost friend.
Taken together, contributions to the page created a portrait of an enthusiastic outdoorsman with varied interests and big dreams. Mr. Collier had ideas for a new Web site but worried that, in the company of tech-savvy MIT students, his concept would be seen as overly simplistic. He quickly mastered winter hiking and had his sights set on climbing Mount Katahdin, in Maine, and Mount Rainier, in Washington State, before taking on bigger challenges. One contributor to the page remembered him as a "cop friend."
"He's one of those cheery officers who is always smiling and making people feel like he's not only there to do his job, but likes doing it as well, and loves the students," the contributor wrote. "Thank you so much for being so brave and protecting us, Sean. I will never ever forget you and what you did."
A member of the MIT Outing Club, who asked to remain anonymous, said in an e-mail to The Chronicle that Mr. Collier hoped to attend law school to pursue his interests in technology and law. He described Mr. Collier as a quiet person with an "altruist's heart."
"I distinctly remember trusting him right off the bat (he's the kind of guy you'd ask to watch your wallet)," he wrote. "It would be exceedingly difficult to imagine him not stepping up and doing the right thing when he had the chance, which unfortunately he did last night."
Awake to Evacuate
Although some initial reports suggested that the Tsarnaev brothers were in the United States on student visas, that does not seem to be the case. Since the September 11, 2001, terror attacks, American colleges have been required to collect multiple pieces of information about international students—for example, they must notify university authorities of any change of address—and those details are collected in a database maintained by the U.S. Department of Homeland Security. But permanent residents of the United States, as the brothers are said to have been, are not subject to that oversight.
The elder of the brothers, Tamerlan, was killed after a shootout with the police early Friday morning in Watertown, which is just west of Boston and Cambridge. He was a part-time student at Bunker Hill for three semesters, from the fall of 2006 to the fall of 2008, according to Patricia Brady, director of communications at the college. She said that he had studied accounting and had not been seen on the campus since 2008.
It is common, she said, for students to come and go at Bunker Hill, which is the largest community college in Massachusetts, enrolling more than 14,000 students. The college has multiple campuses in the Boston area, with its main campus located in Charlestown, a Boston neighborhood.
The younger of the brothers, Dzhokhar, was a registered student at the University of Massachusetts at Dartmouth. He also worked off and on as a lifeguard at Harvard, starting when he was a high-school student and most recently last summer, according to a Harvard official. He was a temporary employee, the official said, and did not have access to the university's facilities outside his duties.
After the Dartmouth campus confirmed that the younger Mr. Tsarnaev was a registered student, it began a controlled evacuation of the campus. Everyone was asked to leave, with state, local, and campus police officers arriving to assist and to "conduct a full investigation," according to a university news release.
More than half of the more than 9,000 students enrolled at the public university live off campus, and more than 90 percent are Massachusetts residents. But the suspect reportedly lived on the campus, in Pine Dale Hall.
Students in that dormitory awoke on Friday to knocks on their doors. Katie Horan, a sophomore, said she had been evacuated by security and police officers just before 8 a.m.
Students didn't know what was going on, why they were being led out, or when they would be allowed back in, Ms. Horan said. She was wearing her pajamas, she said, and had not brought her wallet or driver's license. "One of my friends didn't even have his glasses," she said.
Most Pine Dale residents went to get breakfast in a campus cafeteria, Ms. Horan said, and when Mr. Tsarnaev's face appeared on television screens there, students were shocked. "Everybody was like, 'Holy crap, I know him,'" Ms. Horan said. "One guy was like, 'Oh my God, that kid's in my English class."
Ms. Horan had lived near Mr. Tsarnaev last year as well, she said, and had spoken with him several times. Recalling those encounters now, she said, was eerie. "He was planning it here," she said. "He was thinking about it here. We were in passing with him when he was planning this."
A few students had even talked to Mr. Tsarnaev on the campus on Tuesday, the day after the bombings at the Boston Marathon, said Ms. Horan and her friend Steven Tikellis, a freshman. "Our friends from campus who knew the person, they said he was a nice, really easy-going, friendly guy," Mr. Tikellis said. "They said he was social, nothing out of the ordinary, not isolated."
At 10 a.m., all students at the university received a text message telling them to evacuate the campus. University officials posted information continuously on Twitter and Facebook, coordinating transportation for any students who needed it. They were told to proceed to a parking lot where they could get a ride to Dartmouth High School.
The high school was closed for a break on Friday, but the superintendent and principal were both there to welcome students evacuated from the university. About 500 students were headed there, according to the superintendent's secretary.
Ms. Horan and Mr. Tikellis spent the next couple of hours driving around the edge of the campus in her car. "The whole world is now watching our school," she said. Mr. Tikellis described the scene as a swarm of police officials, campus security officers, and reporters, along with students carrying suitcases, trying to make their way through the confusion.
While people on the campus were stunned, the scene was not chaotic, said the Rev. David Frederici, the university's Roman Catholic chaplain. "It's actually been very organized and calm," he said.
Father Frederici was planning to go to the campus on Friday morning, but he was in touch with an administrator who discouraged him from coming. He went instead to the Newman House, a Catholic student center adjacent to the campus but not technically on it.
"We opened this up as a safe place to go," he said. He e-mailed and sent text messages to students on the Catholic ministry's list and also turned to Twitter and Facebook to spread the word. A handful of students came to the center to wait for rides elsewhere. Father Frederici was helping one student get to another location early on Friday afternoon.
'Don't Let It Be a Muslim'
Meanwhile, news of Monday's bombings had caused unease among some Muslim college students in the Boston area well before the suspects had even been described, much less identified as Muslims from the troubled Russian region of Chechnya.
In fact, one thought crossed Ifrah Inam's mind when she heard about the bombings: "Oh God, don't let it be a Muslim."
On Tuesday, the sophomore in the pharmacy program at the Massachusetts College of Pharmacy and Health Sciences, in Boston, thought briefly about visiting Boylston Street, the site of the attack. She decided not to, in part because she worried what the reaction might be to her hijab.
"You couldn't help but be paranoid," she said from her home in Sharon, a suburb south of Boston.
When she saw the images of the suspects released on Thursday by the FBI, Ms. Inam, 20, felt relief that their appearance did not fit stereotypes of a South Asian or Middle Eastern follower of Islam.
But then, she said, "my heart sunk when I found they were Muslims."
Dan Berrett, Nick DeSantis, Karin Fischer, Sara Hebel, Xarissa Holdaway, Sara Lipka, Andrew Mytelka, Stacey Patton, Ann Schnoebelen, Jack Stripling, Beckie Supiano, and Don Troop contributed to this article.