LONDON — British police investigating the murder of exiled Pakistani politician Imran Farooq in London nearly three years ago said they had arrested a man at Heathrow airport on Monday on suspicion of conspiracy to commit murder. The 52-year-old man, a British citizen of Pakistani origin, whom they did not name, was detained by counter-terrorism officers as he arrived on a flight from Canada and was taken to a West London police station, police added in a statement. Farooq, 50, was a former leader of Pakistan's Muttahida Qaumi Movement (MQM) and had lived in London in self-imposed exile from 1999. He was on his way back from work when he was attacked outside his home in Edgware, north London, in September 2010. A post-mortem gave the cause of death as multiple stab wounds and blunt trauma to the head. A kitchen knife and a house brick used in the attack were recovered at the scene. The MQM, a secular party, has been locked in a battle with various rivals for influence in Pakistan, particularly in Karachi, its main powerbase in the country. Its current leader, Altaf Hussain, is accused of murder in Pakistan and leads his party remotely from exile in Britain. His party is designated a terrorist organization by Canada, a charge it strongly denies. — Reuters