The alleged BTK killer has confessed to at least 10 murders dating back to 1974, law enforcement sources told FOX News.

Dennis Rader (search), who lived in the same Wichita, Kan., area that was home to the BTK victims for more than 30 years, was charged Tuesday with 10 counts of first-degree murder. He is being held on a $10 million bond for the "Bind, Torture, Kill" slew of murders that began in 1974.

The former city's parks department worker was taken into custody and arrested Feb. 25 after authorities tested a DNA (search) sample from his daughter's medical records unbeknownst to her, and were able to match it to blood saved from a 1964 crime scene. Sources told FOX News that investigators then asked his daughter, who lives in Michigan, for another sample to confirm the results.

Authorities are now investigating whether Rader can be linked to other murders that occurred in areas the suspect lived during the '60s, while he was in the Air Force.

For decades, Rader, who is a leader at the Christ Lutheran Church (search) church, allegedly taunted police by sending letters and pictures of his victims to authorities and the media.

Rader was in a Park City enforcement vehicle, with its logo on the door, when he was arrested. The vehicle had been spotted in a surveillance video of a BTK drop-off spot near a Home Depot in Wichita, authorities told FOX News.

FOX News' Rita Crosby contributed to this report.