The Pentagon's top leadership today discounted an errant 2,000 pound bomb as the cause of scores of civilian casualties reported at a village wedding in central Afghanistan but did not rule out the possibility that an AC-130 gunship mistook celebratory gunfire for hostile fire.
"I will tell you that if you happen to be the person on the other end of whatever the weapon that is pointed at you, and it is firing, it is very difficult to know whether that's a friendly muzzle flash or an enemy muzzle flash," said Marine General Peter Pace, vice chairman of the Joint Chiefs of Staff.
US and Afghan officials arrived today at the scene of Sunday night's incident in the central Afghan province of Uruzgan to investigate reports that a bombardment killed 40 civilians and up to 70 others attending an Afghan wedding, US officials said.
The US military said a 2,000 pound bomb that went astray after it was dropped by a B-52 bomber in a strike on a cave and bunker complex in the area around the same time was seen hitting an unpopulated hillside.
But he did not rule out the possibility that an AC-130 gunship that was providing close air support for a US-Afghan ground operation mistook celebratory gunfire at the wedding for hostile fire.
He said the fixed wing aircraft, which carries side-firing cannons, came under anti-aircraft artillery fire and returned fire at six individual locations spread out over many kilometers.
"The only thing I am sure of is at the time the weapons from the AC-130 were being fired at the ground, that the controller on the ground and the air crew in the airplane believed they were returning fire against anti-aircraft weapons, which has happened repeatedly in a particular area and which was reported to be taking place at the time that the AC-130 fired," General Pace said.
US Defense Secretary Mr Donald Rumsfeld expressed regret for any loss of innocent lives.
"These incidents that may occur take some time to sort out," he said, adding that the US-Afghan team had begun the process of interviewing people and establishing what happened.
"It is unclear how much longer it will take, but it could take another day or two," he said.
AC-130 gunships often carry gun cameras that might shed light on what its crew fired at.
The only casualties encountered by US forces were four children -- aged eight months to five years -- who were evacuated to Kandahar for treatment of shrapnel wounds and broken bones.
But a Pentagon spokeswoman said US military personnel saw 19 injured people who were brought from the area to a hospital in Kandahar.
Six of those soldiers came under small arms fire as they were leaving Kandahar in a six vehicle convoy and one US soldier was wounded in a foot.
Mr Rumsfeld did not question the veracity of reports by Afghan officials that spoke of scores of civilian casualties at the village of Kakrakia, saying US forces would not necessarily have been aware of them.
The officials disclosed that the search and reconnaissance operation underway in the area involved 300 to 400 US and Afghan troops, a much larger operation than previously acknowledged.
General Pace said the operation was mounted because US aircraft had come under anti-aircraft artillery fire from the area several times before, and the area was a stronghold in the past of fugitive Taliban leader Mullah Mohammad Omar.