SYDNEY - Two looters were shot dead as a wave of attacks on Chinese-owned shops spread in Papua New Guinea, bringing the death toll to four, reports said Thursday.

The two men were killed and three others were wounded as a mob tried to raid an Asian-owned store in Wabag, capital of Enga province, in the early hours of Tuesday morning police said.

'The men tried to break in and were met by those guarding the store. There was gunfire,' provincial police commander Michael Chare told the National newspaper.

Fearing reprisals by clansmen of the dead and injured, police patrolled Wabag's streets, using loudhailers to urge people to disperse and go home before dusk.

'The situation in Wabag is quiet but tense. There are at least eight Asian shops here and they remain closed,' Chare said.

Asian shops in several towns throughout the country have been attacked over the past week, with protesters and looters accusing them of overcharging and demanding they be taken over by locals.

Two men were killed in raids on shops in the town of Lae on the north coast last Thursday, one shot dead and the other trampled to death in a stampede, police have said.

Enga Governor Peter Ipatas expressed regret at the latest loss of life in Wabag but said looting was illegal and blamed the national government for failing to address 'underlying problems' in society.

'If foreigners are taking over businesses, that is because the government has failed to protect and promote the interests of its people,' he said.

Beijing has urged leaders of the impoverished island nation to bring the situation under control and safeguard the safety and interests of its citizens.

Papua New Guinea's acting Prime Minister Puka Temu on Wednesday apologised for the string of attacks on Chinese-owned shops, labelling the perpetrators 'hooligans and opportunists'.

Parliament on Wednesday voted to set up a special bi-partisan committee of lawmakers to look into the looting, the Post-Courier newspaper reported.

The first Chinese moved into PNG in the late 19th and early 20th century, but few of their descendants remain, while a fresh wave of thousands of Chinese immigrants has arrived over the past 10 years.

Their rapid move into business, along with Koreans and other Asians, has provoked growing animosity from locals, many descended from warrior tribes which had no contact with the outside world until less than a century ago.