The top U.S. commander in Afghanistan says he is “mad as hell” about attacks on Western troops by Afghan soldiers and police – the so-called insider attacks.

General John Allen said in an interview with CBS-TV's 60 Minutes, scheduled to air Sunday night, that “we're willing to sacrifice a lot for this campaign, but we're not willing to be murdered for it.”

Allen said that just as homemade bombs had become the signature weapon of the Iraq war, he believed that in Afghanistan, “the signature attack that we're beginning to see is going to be the insider attack.”

In the latest suspected insider attack, a U.S. soldier and a foreign civilian contractor were killed late Saturday in eastern Afghanistan's Wardak province. At least two Afghan soldiers were also killed.

A Taliban leader told CBS the insider attacks are part of the militant group's new military strategy.

He said the Taliban has its people planted in the Afghan police and the army.

More than 50 international troops have been killed this year in a series of insider attacks. A similar number of Afghan security force members have been killed in such attacks.