The chief of staff to Republican Rep. Steve Stivers of Ohio has resigned after a graphic photo of the aide appeared over the Internet.

Adam Kuhn, a longtime aide to Stivers, submitted his resignation Tuesday.

In a statement to The Associated Press, Kuhn said he was the victim of an attack on Twitter from a woman with whom he had a personal relationship. He expressed regret for what he called "poor judgment in my personal life."

In the last week, the woman tweeted at least one photo of Kuhn's penis to Stivers' Twitter account.

A spokeswoman for Stivers said the congressman had accepted Kuhn's resignation and that the office had no comment on Kuhn's personal life.