At least 11 people have been killed and 45 are missing after heavy rains caused a landslide near an illegal gold mine on the Indonesian island of Sulawesi, officials say. 

The landslide on Sunday in the remote Bone Bolango district in Gorontalo province killed miners and residents living near the mine, Heriyanto, head of the local rescue agency Basarnas, said on Monday. 

“We have deployed 164 personnel, consisting of the national rescue team, police and military personnel, to search for the missing people,” Heriyanto said. 

However, rescuers must walk about 20km (12 miles) to reach the landslide site and were being hampered by thick mud over the road and continuing rain in the area, Heriyanto added. 

“We will try to use an excavator once it’s possible,” he said. 

About 79 villagers were digging for grains of gold in a pit at the small traditional gold mine when tonnes of mud plunged down the surrounding hills and buried them, Heriyanto said. 

He said rescuers pulled out 23 people alive, including six injured, and recovered 11 bodies, including two women and a four-year-old boy. Forty-five others are missing, he said. 

National Disaster Management Agency spokesperson Abdul Muhari said torrential rains that have pounded the area since Saturday also broke an embankment, causing floods of up to 3 metres (10ft) in five villages in Bone Bolango. Nearly 300 houses were affected and more than 1,000 people have fled to safety. 

Indonesia’s National Agency for Disaster Countermeasure warned residents that rain is still expected in some areas in Gorontalo province on Monday and Tuesday and urged people to be alert.