3 NATO troops die in another "insider attack"

(CBS/AP) KABUL, Afghanistan - The U.S.-led military coalition in Afghanistan says three of its troops have been killed by a man in an Afghan army uniform.

A Pentagon official told CBS News that no American troops were hurt in the assault. A fourth soldier is wounded and is not expected to make it.

The attack is the latest in a rising number of disturbing shootings this year by Afghans soldiers - or insurgents dressed as government troops - on the international forces training them to fight the Taliban as the international coalition withdraws.

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NATO said Wednesday the latest attack came a day earlier in southern Afghanistan. It gave no other details.

Similar "insider attacks" have been rising sharply, with 34 of them so far this year. Forty-five coalition members have been killed, mostly Americans.

At least a dozen of this year's attacks have been in the past month, raising questions of a new Taliban strategy.