American troops are investigating whether Saddam Hussein's sons Uday and Qusay were among those killed during a gunfight on Tuesday with US troops in Mosul, Iraq, CNN quoted Pentagon officials as saying.

"We are reasonably certain they could have met their maker," a US official told the channel. "We didn't just stumble across them."

Another US official told CNN that no one was captured at the house raided in Mosul, and that four people were killed.