Conservative MP David Morris said his website has been hacked by an organisation claiming to represent "Freedom for the Mujahideen".
Mr Morris, who represents Morecambe & Lunesdale, said: "I was shocked to discover that my website has been hacked. I have alerted the company who host my website as well as Lancashire Police."
He also tweeted: "My website has been hacked, currently working on the situation please e-mail or telephone until further notice."
A spokeswoman for Lancashire Police said: "We received a report from a complainant relating to a website and an investigation is under way."