Separatist rebels in Indonesia’s Papua region say they have killed at least 13 Indonesian military soldiers after the army sent troops in search of captured New Zealand pilot, Phillip Mehrtens, who was taken hostage in February.

The West Papua National Liberation Army (TPNPB) said its soldiers attacked two Indonesian military posts in the Yal and Mugi districts in Nduga Regency over the weekend, according to a statement.

The statement said the rebels shot dead 13 Indonesian military and police officials in the Mugi district. One body had been evacuated by the Indonesian military, but rebels were still in possession of 12 bodies, the statement added, without providing proof.

In a televised press conference on Sunday, Indonesia’s military said one of their soldiers had been killed while combing the area near where Mehrtens is believed to be held.

Some soldiers were missing, the military confirmed, but the weather had made it difficult to determine their whereabouts.

“We know the location of the pilot, the operation has been escalated but the weather condition in Papua is unpredictable,” military spokesperson Julius Widjojono said.

Separately, the rebels said nine Indonesian soldiers were executed on Sunday after being captured in the Yal district.

The rebels said the attack on the Yal military post was “revenge” for an Indonesian military operation in the area in late March, when troops killed a pregnant woman and two rebel fighters.

A military spokesperson in Papua, Herman Taryaman, denied soldiers carried out the March attack, saying the security forces were protecting civilians who were chased away by the rebels, Reuters reported.

The rebel group said they’d proposed peace negotiations with the New Zealand and Indonesian governments, but for two months their letters had been ignored.

They said New Zealand and the UN had an “obligation to urge the Indonesian Government to stop military operations” and said peace talks could be conducted under a “neutral third party, namely the UN organizational body.”

Mehrtens was captured in February after landing a commercial Susi Air charter flight at the remote Paro Airport in Nduga regency.

The Indonesian military maintains a heavy and controversial presence in Papua, which came under Jakarta’s control following a widely disputed 1969 vote overseen by the United Nations. Unrest in the impoverished but resource-rich region has escalated in recent years as separatist fighters demand independence.

The TPNPB, designated by the Indonesian government as a terrorist group, originally said that Mehrtens would not be released until Jakarta acknowledged Papuan independence and withdrew its troops from the region.

However, they later dropped that demand as a condition of the pilot’s release, and now want to talk with the New Zealand and Indonesian governments to secure his release, according to TPNPB spokesperson Sebby Sambom. (CNN)

•PHOTO: A man, identified as Philip Mehrtens, the New Zealand pilot held hostage by a pro-independence group, stands among the separatist fighters in Indonesia's Papua region, in this undated picture released by the The West Papua National Liberation Army on February 14.

HANDOUT/The West Papua National Liberation Army/Reuters

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