Washington (CNN) -- Republican Rep. Christopher Lee of New York resigned his House seat Wednesday after a report that the married congressman had tried to meet a woman on Craigslist.

"It has been a tremendous honor to serve the people of Western New York," Lee said in a statement posted on his website. "I regret the harm that my actions have caused my family, my staff and my constituents. I deeply and sincerely apologize to them all. I have made profound mistakes and I promise to work as hard as I can to seek their forgiveness."

The statement said that "the challenges we face in Western New York and across the country are too serious for me to allow this distraction to continue, and so I am announcing that I have resigned my seat in Congress effective immediately."

Just before 6 p.m., an announcement read on the House floor said Lee had resigned as of 5 p.m. Wednesday, and the number of the House members decreased by one from 435 to 434.

Lee, who is married and has a son, resigned after the website Gawker published an item reporting that he corresponded with a woman who posted a Craigslist ad and allegedly sent her a bare-chested photo of himself.

The speed of Lee's resignation indicated a culture of zero tolerance by House Republicans for potentially controversial behavior so soon after winning control of the chamber for the first time since 2007.

Lee was first elected to Congress in 2008 from New York's 26th district in the western part of the state, which includes suburbs of both Buffalo and Rochester. He won re-election in November.

CNN's Deirdre Walsh contributed to this story.