Conservative MP and Deputy Speaker of the House of Commons Nigel Evans has been bailed after being arrested on suspicion of rape and sexual assault.
The offences are alleged to have taken place against two men in their twenties in his constituency in Lancashire between July 2009 and March 2013.
Evans, 55, was arrested early on Saturday morning at his Pendleton home and interviewed all day by police before being bailed until 19 June. The house was also searched by officers.
In a statement, Lancashire Police said: "We take all allegations of a sexual nature extremely seriously and understand how difficult it can be for victims to have the confidence to come forward.
"As a constabulary, we are committed to investigating sexual offences sensitively but robustly recognising the impact that these types of crimes have on victims."
Evans came out as gay in 2010 after the launch of a parliamentary group set up to help MPs and staff to be open about their sexuality.
Prime Minister David Cameron and Speaker of the House of Commons John Bercow have been informed of the arrest.
Swansea-born Evans has served as MP for Ribble Valley in Lancashire for more than two decades since first being elected in 1992.
He has held a number of senior positions in the Conservative Party. Between 1999 and 2001 he served as vice-chairman of the party and was appointed Shadow Welsh Secretary under then Tory leader Iain Duncan Smith in 2001.
Three years ago, he was appointed one of three Deputy Speakers of the House of Commons.