A US warplane bombed US special forces and Kurdish civilians in a convoy this morning, killing at least eighteen Kurds and four US troops in a "friendly fire" incident in northern Iraq.
A US warplane bombed a convoy of American special forces and their Kurdish allies as it paused near an area recently captured from Iraqi forces not far from the town of Kalak.
"The latest count I have for you from the Kurdish 'peshmerga' (fighters) side is 18 people killed and over 45 injured," said Hoshiyar Zebari, political adviser to Massoud Barzani, leader of the Kurdistan Democratic Party (KDP).
The US military has said it investigating the incident, which occurred about 30 miles (48 km) southeast of the northern city of Mosul.
The BBC's World Affairs Editor John Simpson said he was travelling in the convoy of eight or 10 cars when it came under air attack as it approached an area recently captured from Iraqi forces near the town of Kalak.
"I've counted 10 or 12 bodies around us, so there are Americans dead. It was an American plane, dropped the bomb right beside us, I saw it land about 10 to 12 feet away," he told the BBC moments after the blast.
A Kurdish source told Reuters that Barzani's brother was wounded in the explosion and was in a critical condition.
The KDP governs two of the three provinces of northern Iraq under Kurdish control since the 1991 Gulf War. Kurdish fighters backed by U.S. forces are slowly advancing out of their enclave towards the Iraqi-controlled cities of Mosul and Kirkuk.
"This is just a scene from hell here, all the vehicles are on fire, there are bodies burning, there are bodies lying around, there are bits of bodies on the ground," said Simpson, who was slightly hurt in Sunday's attack.
A highly placed Kurdish source told Reuters that seven Kurdish fighters, known as Peshmerga, died in the strike, while at least 10 people were wounded, including Wajeeh Barzani. He did not know how many US special forces were killed.
The wounded were reported to have been taken to Arbil, which is southeast of Kalak. Reuters reporters said the city's central hospital had been sealed off.
The US military said in a statement it was investigating the incident, which occurred about 30 miles southeast of the northern city of Mosul.
"Coalition aircraft were conducting close air support missions at the time, and were in coordination with ground forces. The circumstances contributing to the incident are under investigation," the statement from US war headquarters said.
It did not have immediate information on casualties.
US warplanes have been pounding Iraqi positions ahead of the advance on Mosul and Kirkuk. Reuters correspondents in the area said there was a heavy bombardment of the road from Kalak to Mosul on Sunday morning.
There have been numerous cases of so-called friendly fire during the 18-day war in Iraq, killing an unspecified number of US and British troops.