A credible e-mail threat to the two Delaware County Community College campuses in Chester County has prompted school officials to shut down the remaining three locations at least until Monday.

About a dozen e-mails were received about 12:30 p.m. Thursday at the Exton and Downingtown campuses threatening "violence against numerous persons," Sgt. Martin Malloy of the West Whiteland police said yesterday.

Malloy said a search warrant is being served in an attempt to locate the sender of the threatening e-mail. He said they believe, based on the contents of the message, that the person who sent the notes may be a student.

Malloy would not disclose the exact contents of the e-mail.

College officials contacted police as more of the e-mails, sent to college departments, were discovered by employees.

The college, which serves about 10,000 day students, also has campus locations in Marple, Sharon Hill and on Malin Road in Broomall, Delaware County.

"We started to take action about 3 p.m.," said Fran Cubberley, a school associate vice president. Cubberley said the college sent e-mails to all employees, posted a notice on the campus Web site, and used a phone broadcast system to alert students that classes were canceled.

Cubberley said school authorities are playing it "day by day" and will not resume classes until they feel it is safe.

"I think that certainly we made the decision to close all college locations probably in the shadow of what happened at Virginia Tech," said Cubberley, who added the college normally is conservative with security matters.

On April 16, Virginia Tech student Seung-Hui Cho killed 32 and wounded at least 15 during a campus rampage before killing himself.

Contact staff writer Mari A. Schaefer at 610-892-9149 or mschaefer@phillynews.com.

Inquirer staff writer Kathleen Brady Shea contributed to this article.