A Kentucky state representative accused of molesting a teenage girl killed himself on Wednesday, just two days after the allegations were made public, the authorities said.

Representative Dan Johnson, a first-term Republican, took his life on a bridge in Mount Washington, Ky., according to Sheriff Donnie Tinnell of Bullitt County, who spoke to the local WDRB television station. The county coroner, Dave Billings, said that Mr. Johnson “died of a single gunshot wound” and that it was “a probable suicide.” An autopsy is to be conducted Thursday morning.

On Monday, the Kentucky Center for Investigative Reporting published an extensive investigation alleging that Mr. Johnson had sexually assaulted a 17-year-old parishioner at the Heart of Fire Church in nearby Louisville, an evangelical church where he was bishop.

The parishioner, now 21, said that in the early hours of Jan. 1, 2013, after a New Year’s Eve party at the church, she and Mr. Johnson’s daughter slept over at an apartment below the fellowship hall. After falling asleep on a sofa, she said, she woke up to find Mr. Johnson — who was drunk after going to a bar earlier in the night — kneeling over her. He proceeded to kiss her, grope her breasts under her shirt, put his hand down her pants and penetrate her with his finger, she said.