The British ambassador in Yemen has escaped unharmed after a suicide bomber in a school uniform detonated an explosives belt. The blast, which bore the hallmarks of an al-Qaeda attack, took place as Tim Torlot, 52, travelled to work in the Yemeni capital of Sana'a. Yemeni sources said Mr Torlot's armoured car had been travelling through a neighbourhood in the eastern part of Sana'a known to be popular with militants when the explosion happened. The Yemeni Interior Ministry said the bomber - a 22-year-old man - was killed. Security was stepped up around the US and British Embassies following the attack. A Foreign Office spokesman said: "We can confirm that there was an incident in Sana'a this morning. There was a small explosion beside the British Ambassador's car. He was unhurt. No other embassy staff or British nationals were injured. The attack has cast doubts over the effectiveness of the Yemeni government's ongoing crackdown against al-Qaeda militants in the country.