Armed separatists say they attacked soldiers as army was searching for a captured New Zealand pilot.

Separatists in Indonesia’s Papua region say they have killed nine soldiers in an ambush, but the military says one soldier was killed during search operations to find a kidnapped New Zealand pilot.

Indonesian military spokesman Julius Widjojono said on Sunday that soldiers were dispersed to several sites in the search for captured Susi Air pilot Phillip Mehrtens and they were having communication difficulties due to bad weather.

Mehrtens was kidnapped by the rebels at an airport in the remote Nduga district in February.

“As of 2:03pm local time [05:03 GMT Sunday], the information we have is one died,” Widjojono said when asked about the higher casualty numbers. “We have not received any other information because it is difficult to reach the area, especially with the uncertain weather.”

Widjojono said the military will intensify the operation to rescue Mehrtens because they have identified the pilot’s location.

Erratic weather has made the effort challenging, he said.

The West Papua National Liberation Army, the military wing of Papua’s main separatist group, claimed responsibility for an attack on Saturday that they said killed nine soldiers.

The rebels had previously demanded that Indonesia recognise Papuan independence in return for the pilot’s release as well as a meeting with President Joko Widodo facilitated by the international community.

The separatists said Saturday’s attack was an act of defence against military activity in the region and demanded the government instead negotiate for Mehrtens’ release.

“The United Nations and the New Zealand government have an obligation to push Indonesia to stop the military operation,” rebel spokesman Sebby Sambom said on Sunday.

Flying is the only way to reach mountainous areas in Papua, where rebel attacks have risen in recent years.

Papua’s Melanesian population shares few cultural connections with the rest of Indonesia, and the military has long been accused of human rights abuses there.

A former Dutch colony, Papua declared itself independent in 1961, but neighbouring Indonesia took control two years later, promising an independence referendum.

The subsequent vote in favour of staying part of Indonesia was widely considered a sham.