UK on missile terror alert Blair orders security crackdown after aircraft threat · 1,500 troops, police patrol HeathrowNick Hopkins, Richard Norton-Taylor and Michael WhiteWednesday February 12, 2003The GuardianHeathrow was last night being patrolled by 1,500 anti-terrorist police and troops after intelligence warnings identified it as a likely target for an imminent attack by al-Qaida-linked militants armed with anti-aircraft missiles. The move was sanctioned late on Monday after high level meetings at Scotland Yard headed by Assistant Commissioner David Veness, who requested immediate army back-up and support from Heathrow's neighbouring forces, Surrey and Thames Valley. The prime minister was told of...