At least 20 Papuan gold miners were buried in a landslide at PT Freeport Indonesia's tailing area in Tembagapura, Mimika, on Tuesday, a police officer said.
Mimika Police chief Adj. Sr. Comr. Godhelp Cornelis Mansnembra told The Jakarta Post in Timika, the capital of Mimika, the landslide occurred due to two days of heavy rain in Tembagapura.
As of Tuesday afternoon the police had recovered 12 of the victims' bodies, he said.
"I received this information from the search and rescue team at the scene of the accident," he said.
"This is a natural disaster. Authorities have constantly prohibited local miners from prospecting in the tailing area for the sake of their safety. However, they have never heeded the prohibition."
He said the police, aided by security guards from PT Freeport Indonesia and local residents, were still searching for the other victims.
PT Freeport spokesman Mindo Pangaribuan told the Post on Tuesday the landslide was a natural disaster and the victims had carried out their activities without permission.
The victims were not employees of the company and the incident took place outside the company's area, he said.
Pangaribuan said the incident did not disrupt operations in the company's mining area, and that a team had been deployed to assist police in search of the victims.
He added that PT Freeport and the local administration would immediately address the increasing illegal gold mining activities at the tailing area.
"We convey our deepest sympathy over the deaths of the victims," he said.
In a similar landslide in November last year, 13 workers at the gold and copper mine were injured.
The landslide outside the mine in Grasberg did not affect company operations and the victims sustained only light injures, the company said.