Western forces in Afghanistan have begun to train counter-intelligence agents to help root out Taliban infiltrators in the Afghan army and police, as concern mounts over killings by rogue security personnel.
Lieutenant General William Caldwell, head of the U.S. and NATO training mission in Afghanistan, said on Tuesday 222 agents had been trained since the program began last summer, and there was a target of 445 agents by the end of the year.
"We're bringing counter-intelligence personnel into the lowest level of all the organizations ... whose sole mission in life is to look for those who may be attempting to infiltrate in or turn somebody who was already in toward the Taliban," Caldwell said at the Chatham House thinktank in London.
A rogue Afghan border policeman shot dead two foreign soldiers last week, the latest in a string of attacks by Afghan security forces against their NATO mentors.
The shootings highlight a challenge for the NATO-led mission in Afghanistan as it aims to recruit and train a viable Afghan army and police force in time for a planned handover of security responsibility to Afghan forces by the end of 2014.
Rapid recruitment into the Afghan security services has heightened fears about penetration by the Taliban. Caldwell said he was "very concerned" about the problem.
In February, two German soldiers were killed by a man wearing an Afghan army uniform, and last November a border policeman shot and killed six U.S. troops while they were on a training mission.
Earlier that month an Afghan soldier shot three foreign troops, and in August two Spanish police and an interpreter were killed by an Afghan policeman they were training.
Caldwell said another challenge was ensuring Afghanistan's ethnic makeup was reflected in its armed forces, which number some 285,000 people, including the police and air force.
Tajiks were currently over-represented, while there was a shortfall of Pashtuns from southern Afghanistan, the heartland of the mostly Pashtun Taliban.
Despite the difficulties, Caldwell said he was confident of meeting the 2014 handover deadline. The timeline for the transition has looked uncertain in the past year, with 2010 the deadliest year since the conflict began in 2001.
"Many have been asking, 'Are the Afghans going to be ready?' ... my answer is unequivocally yes," he said.