Indonesian police were fired upon by unknown gunmen as they tried to investigate the earlier wounding of two women including the wife of a local human rights campaigner, police said.

It was unclear whether any of the officers had been wounded, Papua police spokesman Daud Sihombing told AFP Wednesday.

"A group of our officers were there to manage the earlier crime scene," he said. "They were shot at by an unknown group." Army Brigadier General Nurdin Zaenal told Elshinta radio that military officers were accompanying police. Zaenal said one soldier who was driving a military intelligence officer was wounded when three bullets hit their car.

The incident happened about 9:30am, Zaenal said from the Papuan capital Jayapura. He blamed separatist rebels for the shooting.

In the earlier incident, the two women, Else Bonai and Merauje, were travelling in a public minivan when they were fired on last Saturday near the border with Papua New Guinea.

Else is the wife of Johannes Bonai, director of the vocal human rights group Els-Ham Papua Barat. The women were wounded in the legs and admitted to hospital, Aloy Renwaring of Els-Ham said at the time. He blamed "professionals" for the shooting.

Police in Papua have said soldiers are suspected of an August ambush near the American-owned Freeport mine in which two Americans and an Indonesian were killed.

The military has denied involvement and blamed separatist rebels. It also threatened to sue Els-Ham for alleging that Kopassus special forces were involved in the ambush.

Police officers investigating that crime scene were also fired upon by what they said were unknown gunmen.

A disorganized and poorly-armed group of separatists has waged a long-running but low-level insurgency in Papua, Indonesia's easternmost province.