COLORADO SPRINGS, Colo. -- Four active duty Army and Air Force personnel were arrested this month in Colorado Springs, accused of possessing and trading child pornography pictures through peer to peer networks, the Colorado Springs police department announced Tuesday.

David Alan, Nicholas Beach, Kyle Mcguire are all from Fort Carson and Andrew Evans is from Cheyenne Mountain Air Force Station.

The computers used were privately owned and not believed to belong to the federal government, said Colorado Springs police Lt. David Whitlock.

Their arrests were part of a sweeping investigation by Colorado's Internet Crimes Against Children unit, which also arrested 11 other men in Colorado Springs this month.

The men range in age from 18 to 70 and live in several Colorado counties.

Additional arrests are pending, which will bring the total number of persons arrested to around 20-25 people, Whitlock said.

Allen, a military police officer, was arrested June 1 when his wife discovered images in his e-mail she believed to be underage girls as well as inappropriate chats with underage girls, police said. Allen's wife turned the computer over to authorities.

McGuire and Beach were arrested after Colorado Springs police, looking into the online trading of child pornography in Colorado via P2P networks, determined that two computers that distributed images of child pornography were located on the Fort Carson Army Base.

The names of the other 11 men arrested, the date of their arrest, and where they were taken into custody are:

Aaron Holt, 24, arrested June 10 at 2000 block of Southgate Road

Ryan Walker, 18, arrested June 11 at 2000 block of Wold Avenue

David Aardal, 70, arrested June 11 at 4200 block of Star Ranch Road

Charles Osborn, 48, a registered sex offender, arrested June 12 at 1422 W. Bijou St

Frank McCrea, 20, arrested June 15 at the Police Operations Center

Michael Bunte, 24, arrested June 15 at the Police Operations Center

Kevin Gauthier, 48, arrested June 17 at 3800 block of Radiant Drive

Stephen Skelly, 24, arrested June 17 at the Police Operations Center

James Wardwell, 66, registered sex offender arrested June 12 at 1028 Arch Street.

Phillip Sheffield, 18, arrested June 17 at the Police Operations Center.

John Hass, 29, arrested June 18 at 300 block of Crestone Drive #11

The Colorado Internet Crimes Against Children task force worked with 15 law enforcement agency affiliates during the course of the investigation. They are the El Paso County Sheriffs Office, Canon City Police Department, Douglas County Sheriffs Office, Ft. Lupton Police Department, Parker Police Department, Eagle County Sheriffs Office, Immigration and Customs, United States Marshals Office, the FBI, US Army Criminal Investigations Division, and the US Air Force Officer of Special Investigations.

Information about internet safety, and photos and descriptions of all the arrested suspects can be found at ColoradoICAC.com.