(ISLAMABAD) -- An exchange of fire between NATO helicopters and Pakistani soldiers in North Waziristan Tuesday left two Pakistani troops injured and questions as to why the firing took place.
According to the Pakistani Army, the helicopters crossed into Pakistan from Afghanistan, prompting soldiers at a nearby post to fire at the aircraft for violating Pakistani air space.
However, the International Security Assistance Force (ISAF) said it received fire from across the border -- while the choppers were still in Afghanistan. A U.S. military official said the helicopters did not return fire until they were shot at for a second time.
The same U.S. military official said ISAF is checking equipment on board the helicopters to see if they crossed the border at any time during the incident.
The Pakistani Army has lodged a complaint and is requesting a flag meeting.
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