In an attempt to communicate more effectively with the student body, Harvard police turned to the Internet this week, posting a request for tips on Tuesday evening's alleged sexual assault and robbery outside Adams House.

Students who logged in to their e-mail accounts yesterday afternoon found a message announcing an "IMPORTANT Harvard University Police Advisory" available by typing "advisory" at the prompt.

The advisory, which will remain posted indefinitely, according to Harvard Police Chief Francis D. "Bud" Riley, consists of a suspect description and information about the incident.

Police have received many calls from students offering thoughts and tips on the case, Riley said.

Detectives are pursuing each lead, said Riley, who declined to comment further on the investigation.

At about 10:45 p.m. Tuesday, an Adams House resident was allegedly approached from behind as she was walking on Linden Street. According to police, the student allegedly was robbed and was the victim of an attempted sexual assault.

Riley said both the victim of the alleged assault and members of the Harvard administration support the decision to post the notice to all students via e-mail.

Students in Adams House received a similar suspect description by mail earlier in the week.

Officers have also been canvassing the area for leads, Riley said.

As a result, Riley said, most students probably knew about the incident before the e-mail posting.

But Riley said improving communication with students has been one of his concerns since his arrival as chief two months ago.

"One of the things that occurred to me was that the students and the Harvard community wanted to know as much as possible," Riley said. "The use of the electronic technology made sense. So we did it."

Riley said he plans to post similar public safety notices in the future on a case-by-case basis.

In the wake of this week's incident, Riley said students should be more careful but not overly concerned.

"Students should be aware that we are in an urban environment, and they should just be more aware about walking alone at night," Riley said. "Sooner or later there are going to be incidents such as this one that are unavoidable.