FREEDOM — A Democratic lawmaker from Waldo County was arrested Monday night after a Maine state trooper allegedly caught him engaged in a sexual act in a van at the West Gardiner Park & Ride.

Brian Jones, 56, of Freedom was charged with indecent conduct and failure to give his correct name, according to Maine Public Safety spokesman Stephen McCausland.

Trooper Lee Vanadestine was doing a routine check of the park-and-ride lot when he spotted Jones and a woman about 10 p.m., according to police.

“Brian Jones would not give his name,” McCausland said. “I think he was arrested primarily because he wouldn’t tell the trooper who he was.”

The Sabattus woman, who owns the van, did identify herself and so was not arrested, McCausland said. The trooper eventually found Jones’ car, with his legislative license plates, parked at the service center across the road. Jones was taken to the Kennebec County Jail late Monday night to be booked.

The first-term state representative is running for re-election this fall. According to the biography on his legislative Web page, he is married with three children and one grandchild. He represents the communities of Burnham, Freedom, Knox, Montville, Palermo, Thorndike, Troy and Unity, and serves on the agriculture, conservation and forestry committee.

Jones said in a statement issued Tuesday night that he knows the allegations will be a source of embarrassment for his family and a cause for concern for his constituents.

“I am deeply embarrassed,” he said. “I am taking steps to address my long-term struggle with alcoholism that I believe is the cause of my behavior. This has been a struggle for me and my family and I am seeking medical treatment now.”

Speaker of the House Mark Eves, D-North Berwick, said that he and others were taking the allegations seriously.

“[Jones] has assured me that he intends to cooperate with the judicial process,” Eves said in a statement. “I extend my support to his family during this difficult time.”

MaryAnne Kinney of Knox, a maple syrup producer who is the Republican candidate for the District 99 seat now held by Jones, said Tuesday night that she considers the Democratic lawmaker a friend.

“We had a gentleman’s agreement that neither of us are going to say anything negative,” she said about their campaigns. “If the pending charges are what they are, the truth will come out … in my opinion, it’s not my business, it’s his.”