Purses and backpacks will be banned and metal detectors will be in place when students return to Delaware County Community College on Wednesday, even though police have not caught the author of two e-mail threats that forced the school to shut on Thursday.

Calling the threat "domestic terrorism" that disrupted thousands of lives, Chester County District Attorney Joseph W. Carroll said he believed that the heavy police presence and security precautions would deter any violence.

Carroll said evidence suggested that the writer of the e-mails sent Thursday, who threatened "to kill everyone at this damn school," intended to disrupt campus operations rather than end lives.

But officials were obliged to take the threats seriously, he said.

"The recent events at Virginia Tech and our collective experience with other school shootings make it impossible to ignore the possibility that a deranged killer would make good on his word," said Carroll, referring to the April 16 slaying of 32 students and staff, and the suicide of the gunman.

"If Virginia Tech taught us anything, it is that we are all vulnerable to violence, to some degree," said Carroll, adding that authorities were working hard to minimize the risks.

Authorities released the content of one of the two "similar" e-mails in the hope that it might produce a tip leading to the sender's identity, West Whiteland Township Police Chief Ralph Burton said. Police said they believe that both messages were written by the same person. Eight faculty members received the messages.

The writer threatened to get two weapons from a friend and unload them at two of the college's five campuses - in Exton and Downingtown - yesterday and today. The message said in part, with the writer's spelling and punctuation: "Take my notice seriously, cause i'm giving 1 chance of survival."

The Exton campus is in West Whiteland.

Law enforcement officials said they have interviewed more than 200 people and have obtained court orders to seize and search student computers. The FBI is assisting in the investigation.

Brent E. Turvey, an Arkansas forensic scientist and author of a textbook on criminal profiling, said the e-mail's tone and content did not appear to reflect an imminent danger.

"At face value, I doubt whether this is a legitimate threat," Turvey said.

The e-mail did not use language that indicated real emotion, or specifics of a grudge, or description of the planned violence. "It suggests that the person isn't that angry - it's an attempt to feign anger," Turvey said.

In contrast, Cho Seung-Hui, the Virginia Tech gunman, provided lurid details of what he intended to inflict on campus. "That's someone who was angry, for real or perceived wrongs," Turvey said.

When classes resume Wednesday, faculty will convene special class sessions to summarize what was supposed to be taught when classes were canceled.

Finals will be given as scheduled next week.

Both Carroll and Delaware County District Attorney Michael Green said they planned to visit the campuses Wednesday. Students would be subjected to searches with metal detectors, and must carry personal possessions in a clear plastic bag, authorities said. Non-uniformed officers will be present on all five campuses in Delaware and Chester Counties.

"I'm missing out on a lot of classes, and stuff that needs to be taught," said Jessica Gerardi, 21, of Springfield, Delaware County, who is majoring in science. "As much as I like being home, I'd rather be in school."

Veronique Johnson, 23, a resident of South Africa who is here on a student visa and living in Villanova, said she believes that the college did not learn much about communication from the Virginia Tech massacre.

"Nobody gave us notice," she said, adding that friends had to text-message each other. "I still don't know what the threat is about."

Jerome "Jerry" Parker, president of the college, which employs 701 full-time and adjunct faculty members for about 10,000 students, said he believed that most students received automated notifications but that some students may not have supplied contact information.

"We need to keep the database up-to-date," he said.

Sarajane Sein, 19, of Collingdale, described the last several days as nerve-racking because she booked a trip to North Dakota the weekend of May 13, after finals.

"I didn't know if I was going to have to scramble to change my plans," she said.

"The more we're out, the more this person wins," said Sein, a first-year liberal arts major.

"I think it would be better if the police find him," she said, "I'm not sure what graduating seniors might do to him."

"If this is what they need to do to assure the safety of myself and others attending DCCC, then I'm willing to cooperate," said Isabella Klinghammer, 19, of Havertown, a nursing major.

Saying that "there is a need to make an example of him in order to deter others," Carroll said the investigation would continue "until the person responsible is in custody."

Anyone with information is asked to call a special tip line - 610-594-9057 - or e-mail detectives@westwhiteland.org.

Contact staff writer Kathleen Brady Shea at 610-701-7625 or kbrady@phillynews.com.