This may be a sign of things to come:

Firing by Pakistani troops forced two U.S. military helicopters to turn back to Afghanistan after they crossed into Pakistani territory early on Monday, Pakistani security officials said.

The incident took place near Angor Adda, a village in the tribal region of South Waziristan where U.S. commandos in helicopters raided a suspected al Qaeda and Taliban camp earlier this month. "The U.S. choppers came into Pakistan by just 100 to 150 meters at Angor Adda. Even then our troops did not spare them, opened fire on them and they turned away," said one security official. The U.S. and Pakistani military both denied that account, but Angor Adda villagers and officials supported it.

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