A former police officer accused of sexually abusing 14 boys in four states was sentenced Wednesday to 31 years in prison

Assistant U.S. Attorney Peter Deegan called Donald W. Rager, 41, "one of the more prolific sexual offenders this office has encountered."

Prosecutors said Rager groomed his victims through Internet chat rooms and instant messaging. He had physical contact with most of them.

Rager produced video recordings of sex with the victims, many of whom were abused multiple times during a session, prosecutors said.

Rager, formerly of Grayslake, Ill., pleaded guilty in June 2007 to interstate travel with intent to engage in illicit sex with a minor, production of child pornography and interstate transportation of child pornography.

In the case, Rager was accused of taking a 13-year-old boy to a Dubuque hotel in February 2006 after contacting him in an Internet chat room.

Rager videotaped himself having sex with the boy and showed the boy other videos of men having sex with minor boys, prosecutors said.

The boy reported the abuse in April 2007. Rager was arrested on May 18, 2007, after he went to Dubuque to meet with the boy again.

Besides traveling to Dubuque, Rager traveled to sites in Illinois, Indiana and Wisconsin where he sexually abused 13 other teenage boys, prosecutors said.

Rager also used a webcam to engage in cybersex, and used the Internet to sent nude pictures of himself to his victims and child pornography to other adults.

Prosecutors said Rager also was involved with a man from London who abused a 10-year-old boy. Rager watched the abuse over the Internet and broadcast it live by webcam, prosecutors said.

The man from England and three others have been charged by English authorities.

Rager is a former part-time officer in Grayslake, a suburb of Chicago where he also operated a security business.