The offices of Deputy Speaker Nigel Evans were searched by police yesterday in connection with an investigation into allegations of rape and sexual assault.
Commons Speaker John Bercow said the offices were searched after an order was granted by Preston Crown Court on Thursday. He said he had been consulted before officers entered Parliament.
A spokesman for Lancashire Police said: "We have confirmed that we have searched offices in London in connection with the investigation but it is inappropriate to comment any further other than to say that we have gone through all the appropriate and necessary procedures before taking this step."
In a statement to MPs at the start of today's sitting, Speaker Bercow said: "I wish to report to the house that the rooms of a member were searched yesterday pursuant to a warrant issued by the circuit judge in Preston Crown Court on 16 May. The warrant related to the investigation of a serious arrestable offence."
Mr Bercow continued: "I should remind members, as did my predecessor in 2008, that the precincts of parliament are not a haven from the law.
"In accordance with the protocol issued by my predecessor on 8 December 2008 on the execution of search warrants within the precincts of the House of Commons, I considered the warrant personally and was advised by officers of the house that there were no lawful grounds on which it would be proper to refuse its execution.
"In addition, as provided for in paragraph six of the protocol, I consulted the Attorney General and the Solicitor General who concurred in this advice. I am very grateful to them. The Clerk of the House was kept fully informed throughout, and also concurred.
"The Serjeant at Arms and Speaker's Counsel were present when the search was conducted. Undertakings have been given by the police officers as to the handling of any parliamentary material until such time as any issue of privilege is resolved.
"The investigation is continuing and it would not be right to comment further. I will not take questions on my statement."
Common have been turned off for legal reasons.