As security forces struggled to restore order in Papua after three people were shot to death on Wednesday in the province’s capital of Jayapura, unidentified gunmen killed another three people in Timika, the nearest town to the world’s largest copper and gold reserve, on Friday.

A contract worker of PT Freeport Indonesia, a local unit of US gold and copper giant Freeport-McMoran, was killed along with two local residents of Timika, some 450 kilometers west of Jayapura, or around 3,000 kilometers east of Jakarta.

“The authorities have so far been unable to identify the perpetrators. The shootings took place just a few miles from a similar incident that happened on Oct. 14,” Freeport spokesperson Ramdani Sirait said.

The incident saw unidentified gunmen open fire at a Freeport truck, killing three workers and badly injuring three others.

In 1967, four years after Indonesia annexed Papua from the Dutch, Freeport opened the region’s first gold and copper mining operation at the Grasberg mine near Timika.

A recent string of deadly incidents in the country’s most remote and underdeveloped province probably constitutes the most serious situation the region has faced in the past 10 years.

Papua police chief Inp. Gen. Bikman L. Tobing said on Friday that the police were still pursuing the perpetrators of Wednesday’s killing of three supporters of a Papuan separatism movement in Abepura, Jayapura.

The bodies of two of the victims were discovered near an Indonesian Military (TNI) post on Thursday after the Third Papuan People’s Congress, which advocated for Papuan independence from Indonesia, was forcefully dispersed by police officers and TNI soldiers.

Outgoing National Police spokesman Inp. Gen. Anton Bachrul Alam said he could not confirm circulating reports of more casualties in the shootings.

“We’re still waiting for an update, but the three victims are confirmed and their bodies recently underwent autopsies.”

He also denied any involvement of the security forces in the killings.

The police, according to Bikman, arrested six supporters of the separatist movement for alleged insurgency and possession of firearms.

They are Forkorus Yoboisembut, who during his speech at the movement’s congress declared West Papua an independent state; Selpius Bobii, the organizer of the congress; and their assistants Edison Gladius Waromi, Dominikus Sorabut, August Makbrawen and Gat Wenda.

Bikman said that the police had released around 300 Congress participants who were earlier arrested.

“The security forces tolerated the supporters as they expressed their opinions in the Congress even though they didn’t have approval to do so. It was not until the event ended that we moved in to disperse the crowd,” Bikman said.

The Congress participants hoisted the banned Bintang Kejora (Morning Star) separatist flag during the congress, proclaiming a West Papuan state to be headed by Forkorus Yoboisembut.

Following the dispatch of an outfit of security forces to Papua late Thursday, led by National Police chief of security maintenance division Comr. Gen. Imam Sujarwo, the situation in Jayapura had gradually returned to normal, with business activities back to normal and children attending school.

The increasing violence in Papua came amid repeated calls from politicians and officials for the government to renegotiate its contract with Freeport. The government said that the contract, renewed in 1991 and due to expire in 2021, constituted a raw deal for Indonesia.