A man has been arrested in connection with the murder in London of an imam who was a critic of Syrian President Bashar al-Assad, police said Monday . Abdul Hadi Arwani, 48, was found in his car with gunshot wounds to the chest in Wembley, northwest London, on Tuesday . The investigation into his death is being handled by counter-terrorism police. Scotland Yard said a 46-year-old man had been arrested on suspicion of conspiracy to murder and remains in police custody. Arwani reportedly fled Syria as a teenager after surviving the 1982 Hama massacre, in which the current president's father Hafez al-Assad sent troops to brutally crush an Islamist uprising. From 2005 to 2011 Arwani was a preacher at a mosque in Acton, west London. Police say they are "open-minded" about the motive for his killing.