About 20 people have died after a truck carrying acid to Glencore's Mutanda Mine in the Democratic Republic of Congo collided with two other vehicles, Glencore says.

The accident occurred on Wednesday evening local time about 50km from the copper and cobalt mine in the country's southeast.

The truck was owned by a logistics company contracted by the mine, Glencore said, without giving its name or any other details on whether those who died were all workers at its mine.

Glencore said in an emailed statement to queries from Reuters that it "will continue to work with the logistics company and relevant government agencies, including the emergency services to provide support".