FORT COLLINS, Colo. -- More than 100 photos of five women that may have been taken from Web sites were superimposed on sexually graphic images and sent to the women, police said Wednesday.

Police spokeswoman Rita Davis said photos of the women's faces were probably taken from two social-networking Web sites, facebook.com and webshots.com, and from the University of Colorado Athletic Department Web site.

University spokesman Dave Plati said the school had not been contacted by authorities or any students about misuse of Web photos. He said no policy changes were under discussion as of Wednesday.

Facebook.com and webshots.com did not immediately respond to e-mail messages seeking comment.

The women's photos were not sexual in nature but were combined with graphic photos by someone skilled in the use of computer publishing software, Davis said.

She said altered photographs have been sent to a woman in Fort Collins and four women in Boulder beginning in September. Some of the women were student-athletes at the university, she said.

The photos were mailed or were left at the victims' homes or on their cars. Some were accompanied by written messages, Davis said.

DNA samples recovered from at least two packets were similar, she said. Forensic experts are able to extract DNA from the adhesive part of an envelope, if it was licked to seal it.

Davis said the perpetrator could face felony stalking charges.

Detectives have identified 10 other women whose photographs were superimposed on graphic images, but it was not immediately clear whether the bogus photos were sent to them.

Anyone with information regarding the case is asked to Detective Kevin Cronin of Fort Collins police at (970) 221-6529.