The death toll after a landslide at an illegal mine in western Indonesia was raised to 13 on Sunday, an official said, as search efforts for any further victims ended.

Heavy rains caused a landslide at a remote illegal mining site on Thursday evening in West Sumatra province on Sumatra island, where rescue workers had to walk for hours from the nearest village to reach the area.

Provincial disaster mitigation agency spokesperson Ilham Wahab said 13 people were found dead, while 12 others were injured, raising the death toll by two.

"Since all 25 reported victims have been found and evacuated, we decided to close the search and rescue operation," Ilham said.

But he said a public reporting post would remain open for the next seven days to allow families to report any missing relatives to authorities.

Unlicensed mines are common across the mineral-rich Southeast Asian archipelago, where abandoned sites attract locals who hunt for leftover gold ore without proper safety equipment.

Indonesia is prone to landslides during the rainy season, typically between November and April, but some disasters caused by adverse weather have taken place outside that season in recent years. (AFP)