2 U.S. troops killed in Afghanistan killed in apparent insider attack

KABUL, Afghanistan The U.S. military says two of its service members have been killed in an apparent insider attack by an Afghan police officer.

The U.S. force in Afghanistan says in a statement that a man wearing an Afghan police uniform turned his weapon on U.S. service members in Uruzgan province. U.S. forces spokeswoman Maj. Lori Hodge says the attack happened before noon on Thursday. She declined to give further details and said it was not clear yet if the attacker was an enlisted police officer or an insurgent disguised as a police officer.

The statement says the attack is being investigated. A NATO spokesperson told CBS News the attacker was still at large later Thursday. The official would not comment on the specifics of current joint force operations in the area where the attack occurred, but said they had "by and large returned to our normal tempo" across the country after temporary restrictions were lifted last month.

At least 53 foreign troops have been killed by Afghan forces already this year - 33 of them Americans. Thursday's was the first such attack on NATO forces since September, and the first since the Afghan government launched a large-scale push to re-screen thousands of security forces, trying to identify infiltrators or those who might not be considered secure.

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Thursday's attack came just a day after the leader of the Afghan Taliban, Mullah Mohammad Omar, released a statement saying insurgents would increase the number of insider attacks against coalition and Afghan forces.

In an emailed statement congratulating Muslims as they prepare to celebrate the Eid al-Adha holiday, Mullah Mohammad Omar urged "every brave Afghan in the ranks of the foreign forces and their Afghan hirelings ... to strike them."

"Jihadist activities inside the circle of the state militias are the most effective stratagem. Its dimension will see further expansion, organization and efficiency," he said. "Increase your efforts to expand the area of infiltration in the ranks of the enemy."

The surge in insider attacks is throwing doubt on the capability of the Afghan security forces to take over from international troops ahead of a planned handover to the Afghans in 2014. It has further undermined public support for the 11-year war in NATO countries.

The attacks have not been limited to members of the NATO-led international coalition. More than 50 Afghan members of the government's security forces also have died this in attacks by their own colleagues.

Afghan officials said last weekend that an officer and a cook had attacked their police colleagues in an assault coordinated with insurgent fighters that left six dead in the country's south.