A landslide at an illegal gold mine in western Indonesia has killed at least 15 people and buried dozens of others in the abandoned pit with rescue workers struggling to locate the missing, officials said Friday. 

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.

The landslide hit a remote site in West Sumatra province on Sumatra island Thursday evening after heavy rains in the area, provincial disaster mitigation agency spokesperson Ilham Wahab told AFP.

"The information we can provide was that a landslide occurred at a gold mine last night, causing several people to be buried. Efforts to search for the victims are ongoing," he said.

Ilhan added that 15 people were killed and three injured, with rescuers searching for 25 others. 

Footage seen by AFP showed rescuers loading one of the dead into an ambulance near the disaster site in the district of Solok.

The Solok district disaster agency said in a statement sent to AFP that the landslide took place at an abandoned "illegal" mine.

"The landslide location is on an old mining pit that had been abandoned by previous miners," it said.

Ilham said all activities at the site had been halted as search efforts for the missing were ongoing.

- Arduous search effort -

Search efforts were being hindered by the remote location, with rescuers including police officers, soldiers and civilians having to walk for hours from the nearest village to reach the area, Ilham said.

"The location is quite far, the terrain is tough. This has hampered evacuation efforts but people are helping so that this evacuation process can be carried out quickly," he said.

The Solok district disaster agency said in its statement that the area had no mobile phone signal, making it hard for rescuers to communicate with each other.

Agency official Irwan Effendy said "the victims include people who conducted manual gold mining activities".

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.

In July, at least 27 people were killed after a landslide struck near an illegal gold mine on the central Indonesian island of Sulawesi.

In May, at least 15 people died after landslides and flooding in South Sulawesi province swept away dozens of houses and damaged roads.

A landslide in the same province a month before killed 20 people.