Troops were shot dead by locals including a police chief and his men as attacks on Nato troops by 'allies' increase
Afghan police inspect vehicles at a checkpoint in Qirshke. Photograph: Sher Khan/EPA
Six US soldiers were shot dead on Friday by Afghans, including police, in southern Helmand province – a grim reminder of the growing threat foreign forces face not just from the Taliban but also from their supposed allies.
It was the bloodiest single day for foreign troops in the province since six British soldiers were killed by a roadside bomb in early March.
Three US Marine Corps special operations troops were shot dead in the early hours of Friday morning in Sangin district, a northern corner of the province that has seen heavy fighting. The killers were an Afghan police commander and some of his men, who had invited the US officers to join them for a meal and to discuss security, Afghan officials said.
Then in the evening, an Afghan man shot dead three other foreign soldiers who worked on a joint base with him, the Nato-led coalition said. It does not reveal nationalities of soldiers killed during operations, but Afghan officials said the men were from the US.
"The attack happened in police headquarters of Garmser," said Daoud Ahmadi, spokesman for the provincial governor, referring to a district about 40 miles (60km) south-west of the provincial capital. One other foreign soldier was also injured, he added.
The Taliban has claimed reponsibility for the attack. "Last night after prayer time around 9pm, they were just coming out of the mosque, and a policeman opened fire on the Americans outside the district police headquarters," said Taliban spokesman Qari Yousef Ahmadi.
The shooter has been arrested, Nato said, but added that he was not wearing a uniform at the time of the attack, leaving open the possibility he was a civilian employee on the base. But Farid Farhang, spokesman for the provincial police chief, said the man was from a much-criticised auxiliary police unit, usually trained by special forces. "All I know is that he was from the Afghan local police," Farhang said, adding that an investigation was underway. The attacks were the third and fourth times in less than a week that Afghans have turned on their mentors or colleagues.
On Tuesday, two Afghan soldiers killed a US soldier and injured two others in eastern Paktia province, and on Thursday two other Afghan soldiers opened fire on a group outside another base in the east, although the only person killed was one of the shooters.
So far this year 37 soldiers and military contractors have been killed in 27 such attacks, far outpacing the toll in 2011. They have become such a commonplace threat that some foreign units are watched by armed "guardian angels" from their own ranks.
In a sign of growing concerns about the frequent shootings, President Hamid Karzai issued a rare condemnation of the deaths of foreign soldiers, and ordered an investigation into shootings in Helmand and Paktia. "The enemy who does not want to see Afghanistan have a strong security force, targets military trainers." Karzai said in a statement that also described the shooters as "terrorists in Afghan security uniform".
Nato commanders argue that the attackers account for only the tiniest portion of security forces, now more than 300,000 strong, and say many are driven by personal grudges rather than loyalty to the Taliban or other insurgent groups. But the shootings are disproportionately damaging to morale on the critical mission to train the Afghan police and army as foreign forces head home.
Two British soldiers were also killed within the space of 48 hours in Helmand this week. Their deaths bring the number of UK soldiers killed in Afghanistan since 2001 to 424.
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