In Afghanistan, three British soldiers were killed and several others were injured when an attacker, suspected to be an Afghan soldier, fired mortar during a military patrol in southern Helmand province this morning. <br/><br/>The NATO-led International Security Assistance Force (ISAF) confirmed in a statement that three of its soldiers were killed and several others were injured in the attack. It said, a joint ISAF and Afghan Ministry of Defense team is investigating the incident.<br/><br/>Afghan Defense Ministry spokesman General Mohammad Zaher Azimi said that the suspected soldier escaped and is being sought. He said that the motive of the attack was not yet clear. NATO commander General David Petraeus expressed condolences to the families of the victims and called for unity in the fight to bring security to Afghanistan. <br/><br/>Five British soldiers were killed by an Afghan policeman in the same Helmand province in November last year. There are more than 9,000 British soldiers based in the province. The British troops are part of 1,40,000 US and NATO personnel currently stationed in Afghanistan.