An Iraqi soldier has fired into a group of US soldiers, killing two of them.

In the first US fatalities since the end of combat operations in the country last week, nine other US troops were injured when the man opened fire in an army compound near the Iraqi city of Tuz Khurmatu in Salaheddin province.

Iraqi and US troops had been playing a sports match when the Iraq soldier started firing after an argument developed over the rules of the game.

The shooter, who has been named as Soran Rahman Saleh Wali, was then shot dead by other Americans.

A high-level investigation has been opened into the fatality, which military officials have described as an isolated incident, not likely to happen again.