British Prime Minister, David Cameron gave an ultimate authority to British Special Air Service (SAS) to target the Islamic State (IS) militants in Syria and Iraq, British intelligence sources told Al Bawaba News Sunday. Amid growing threats to Britain, SAS was given the ultimate authority to kill or arrest IS militants' leaders including the mastermind behind the Tunisian beach massacre that claimed the lives of British tourists, Daily Mail newspaper said. Elite British forces are expected to deploy 100 of its personnel along with US Special Forces and Navy troops in Syria and Iraq. Special Air Services, British Special Boat Services with British Intelligence and British government communications (the British Government wiretapping services) will target IS and other terrorist groups that pose a threat to Britain, according to press reports. Last week, Cameron pledged a wide response for the death of 30 British tourists by IS leader Saifuddin Rizqi, at the Tunisian beach resort Sousse.