Northbridge, MA --- A retired Marine who allegedly slipped "date rape" drugs to his teen daughter's slumber party pals and filmed himself raping the girls has been on the lam since his daughter turned over tapes of the disturbing attacks, police said.

"He gave them some kind of drug that would knock them unconscious and he would rape and sexually abuse them while he videotaped," Northbridge Police Chief Thomas Melia said of 48-year-old Peter Gagnon. "The victims did not know what happened to them." .

Gagnon, a cab driver for a Grafton company, allegedly repeatedly raped six different girls, ages 10 to 14, over the past six months. He fled May 19 - the day his 14-year-old daughter went to police with a gray metal strongbox containing nine tapes of the alleged sex crimes, court papers show. Police wouldn't say if his daughter is one of the victims. .

Gagnon was questioned in Mississippi for similar allegations and was still on the loose last night. .

"These were very offensive types of acts," said Melia, who viewed the tapes. "These girls were all friends with Mr. Gagnon's daughter. Sometime prior to the acts, they were drugged." .

Melia said the tapes depict Gagnon, in plain view of the camera, having sex with the clearly unconscious girls. Police are unsure exactly what type of drugs the girls were given but suspect they were one of the so-called "date rape" drugs. .

Last week, police searched his condo, which he shared with his daughter, and seized a Panasonic camcorder, a Nikon camera, film, two videotapes, a computer and disks, court papers show. Melia said it's unknown if any of the tapes were broadcast on the Internet or if Gagnon may have been showing or selling them. He faces 38 charges, including 20 counts of rape, 14 counts of rape of a child under 14, and four counts of rape of a child 14 or over.