JAKARTA - Armed rebels killed at least seven people at a gold mine in the remote highlands of Indonesia's Papua this week, authorities in the area said on Wednesday.

The incident occurred in the mountainous district of Yahukimo on Monday, with authorities still searching for more casualties, Faizal Ramadhani of the Papua police and military task force told Reuters.

A 90-minute shootout ensued between rebels and authorities as security forces evacuated 20 people from the area, said Faizal Ramadhani of the Papua police and military task force

A 90-minute shootout ensued between rebels and authorities as security forces evacuated 20 people from the area, Faizal said.

The West Papua National Liberation Army (TPNPB) claimed responsibility for the attack in a statement, saying it had killed seven intelligence officers that were posing as gold miners. The group also reiterated its warning to all non-indigenous Papuans to leave the area.

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Separatist rebels have for decades wages a low-level guerrilla war for independence in resource-rich Papua, with the frequency of deadly skirmishes increasingly in recent years as rebel groups have become more skilled at obtaining sophisticated weapons through raids and black-market trades.

The conflict began after a controversial 1969 vote that was overseen by the United Nations which saw the former Dutch territory brought under Indonesian control.

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This February, a TPNPB rebel group in the adjacent highland district of Nduga kidnapped New Zealand pilot Phillip Mehrtens. The Susi Air pilot is yet to be released.