Sydney, Sep 16 (IANS) At least 20 people have been killed in heavy fighting that has erupted between two tribes near a gold mine in Papua New Guinea, while women, girls, the elderly, and young boys rushed to escape the area, reports said on Monday.

The fight in the Porgera Valley in Enga province, home to one of the country's largest gold deposits, started last week when two factions of illegal miners fought among themselves and one faction killed two men from the other faction, Xinhua news agency reported quoting the local newspaper Post-Courier.

About 20 people have been killed, including two local mine workers, and the number increased steadily each day, Post-Courier reported, adding that Porgera has seen a mass exodus of more than 5,000 people.

Police Commissioner David Manning has declared emergency orders to safeguard infrastructure and residents in Porgera due to "escalating law and order issues," local newspaper The National reported.

Police would be increasing the legitimate use of force to remove combatants in order to protect critical infrastructure including the Porgera Mine, Manning said.

"Security personnel will use legitimate lethal force where appropriate to protect the innocent, meaning that any person carrying an offensive weapon in public will be considered a threat and dealt with accordingly, with force," Manning said. "This worsening situation is caused by illegal miners and settlers who are using violence to victimize and terrorise the traditional landowners."

"We have 122 security personnel on the ground, including mobile squad, dog squads and Sector Response Unit as well as personnel from Papua New Guinea Defense Force," he said.

Enga Governor Peter Ipatas on Sunday called on the government to implement a state of emergency due to a surge in tribal violence in the Porgera Valley over the past few days.

"The violence has led to the loss of many innocent lives, displacement of people, property destruction and heightened fears for the safety of local residents and businesses," he said.