JAYAPURA, INDONESIA (AFP) - Three people were killed by Papuan rebels on Monday (June 25), Indonesian authorities said, in the latest violence to hit the restive region ahead of regional elections.

The separatists fired on a small plane carrying 15 police officers - travelling to oversee the polls - just after it landed at Nduga in the centre of the province, Papua military spokesman Muhammad Aidi said.

The plane's pilot was injured in the attack, he added.

Several rebels then killed a trio of street vendors as they fled the scene, spokesman Aidi said.

"As they were fleeing, they shot and attacked vendors near the airport," he said.

"Three of them were shot dead, while another was seriously injured."

A Papua police spokesman said authorities were looking for the shooters.

The incident comes days after a pilot on another plane was shot and injured at the same airport.

Indonesia holds regional elections on Wednesday that are seen as a bellwether for the 2019 presidential polls.

Papua, on the western half of New Guinea island, has been the scene of a simmering insurgency since it was annexed by Indonesia in the late 1960s.

US-based firm Freeport McMoRan's gold and copper mine has been a frequent flashpoint in the struggle for independence and a bigger share of the region's rich resources.

In April, an Indonesian soldier and at least one separatist rebel were killed near the huge mine.