British police have arrested a suspect in the murder of lawmaker David Amess, according to local media and a source close to the investigation.
Ali Harbi Ali, the son of a former media adviser to a Somali prime minister, was arrested under anti-terrorism laws following the killing of Amess.
A lawmaker in British Prime Minister Boris Johnson's Conservative Party, Amess was stabbed repeatedly while meeting constituency voters on Friday in a town east of London.
Police said they arrested a 25-year-old British man at the scene on suspicion of murder and believe he acted alone.
A British source close to the investigation later named Ali as the detained suspect.
Ali's father told The Sunday Times that his son had been arrested in connection with the murder, and in an email to Reuters called the situation "unprecedented and horrific."
He added, "Due to the ongoing early investigation I am obliged and commanded not to talk about it."
British police searched an address linked to Ali in north London on Sunday.
In a statement released via London police, Amess' family said they were "absolutely broken," but asked people to "Set aside hatred and work towards togetherness... Whatever one’s race, religious or political beliefs, be tolerant and try to understand."
The killing comes five years after the murder of Jo Cox, a lawmaker from the opposition Labour Party, and has prompted a review of politicians' security.