Dili – East Timor expressed regret Wednesday over two Australian policemen injured in a mob attack by youths overnight, the latest unrest to hit the tiny nation.

"The government is very saddened that violence is still ongoing," second deputy prime minister Rui Maria de Araujo told a press conference in Dili. He confirmed that three youths had been arrested by international police for the attack near Dili's Comoro neighbourhood on Tuesday.

Portuguese police told the Lusa news agency that the clash took place after Australian police tried to break up a battle between two groups of around 30 rock-throwing youths in an area located near a refugee camp.

Australian police fired live rounds into the air after coming under attack and called in Portuguese police reinforcements who fired rubber bullets to disperse the crowd, Lusa reported. The mob also destroyed three patrol cars used by the Australian police.

Some 82,000 people are living at camps set up in Dili for those who were displaced by a wave of violence by machete-wielding gangs which swept the former Portuguese colony in May, killing at least 21 people.

East Timor invited a 3,200-strong international peacekeeping force to the country of around one million people in the wake of the unrest, which was sparked by infighting among factions in the military and police.