Police have charged a former non-profit executive and law firm administrator with attempting to arrange a sexual encounter with a young girl.

Scott R. Swirling of Gaithersburg, whose online biography says he once led the American School Counselor Association, was arrested Thursday as part of an undercover sting run by the Child Exploitation Task Force in the District, authorities said.

According to a criminal complaint filed in the District’s federal court, Swirling responded to an online advertisement on Craigslist. He exchanged sexually explicit instant messages and e-mails with an undercover D.C. police officer he thought was the father of a 12-year-old girl, the complaint said.

Swirling, 61, and the undercover officer arranged to meet in the District on Thursday, according to court records. In their exchanges, according to the complaint, Swirling write that he was “a bit concerned about a sting.” He repeatedly asked for a photo of the undercover officer’s daughter, writing: “Is there any chance I can get something from…the other end…with today’s date.”

After another officer sent a photo of the “purported child” with a message addressed to Swirling, he agreed to meet, according to the complained. When he arrived, he was arrested, according to the complaint.

The complaint was first reported by the Washington Examiner.

Swirling is listed on his company’s web site as president of the Swirling Group, a project and construction management firm. Swirling’s attorney, Shawn Moore, declined comment.