After closing for four days because of an anonymous threat, Delaware County Community College is discouraging backpacks and purses on its five campuses for the balance of the spring semester, and is asking that personal belongings be placed in clear plastic bags, according to The Philadelphia Inquirer.

Nearly a week after the sender of two anonymous e-mail messages threatened “to kill everyone at this damn school,” the college reopened with police officers and a bomb-sniffing dog on hand. Jerome S. Parker, the college’s president, said in a statement on the college’s Web site that administrators were working with the Federal Bureau of Investigation and local authorities, and he announced a $5,000 reward for information about the threats. The e-mail messages were signed “J Feathers.” —Lawrence Biemiller