Nyack College students are on high alert as reports of a suspicious man roaming the campus continue to spread. 

Some students first encountered the alleged intruder on Sept. 23. They said their conversations with the man were pleasant, but suspicious enough to report to campus security. On Oct. 2, campus security spotted the man on surveillance footage that they were reviewing in an unrelated matter.

Police describe the man, seen roaming the hallways of at least two dorms--even going in and out of rooms--and trying to open the locked doors of the campus center, as being in his late 20s to early 30s. The campus is now plastered with fliers that warn students to stay alert.

South Nyack Police say, as of now, they don't believe the man is dangerous, but many students say they won't feel completely comfortable until he is caught.

Anyone with information about the man's identity is asked to call police at .