In the video player: Live coverage from Douglas Tuesday, May 23

DOUGLAS, Ariz. (KGUN) DOUGLAS, Ariz. (KGUN)Douglas Police Department says investigators have determined the fires that damaged two historic churches Monday and early Tuesday were intentionally set.

According to police, investigators identified Eric Ridenour as a person of interest, and the Douglas Police and the Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF) determined probable cause to execute a search warrant in Ridenour’s home outside Douglas.

During the search, Ridenour was detained and later arrested by ATF as a suspect. He was taken to Cochise County Jail and will be transferred into federal custody. Ridenour will be charged in federal court.

A spokesperson from the U.S. Attorney’s office has confirmed with KGUN 9 that they expect more information will be released to the public Thursday. Filings in court are not expected until Thursday.

Douglas Police, Douglas Fire, ATF, Gilbert Fire and the FBI are involved in the investigation.

Police say they have yet to determine a motive behind the fires. The investigation remains ongoing.

St. Stephen’s Episcopal Church and First Presbyterian Church, both more than 100 years old, were damaged by smoke and flames.

RELATED: Douglas Mayor Donald Huish on church fires: “It does look suspicious”