RIO DE JANEIRO (AP) — A dam burst at a mining operation in southeastern Brazil on Thursday, submerging nearby homes and vehicles. Authorities said there are dead and missing but have not yet given any figures.

Rescue teams were searching for survivors or bodies, and residents living in an area downhill from the dam were told to evacuate to higher ground.

The Civil Defense agency of Minas Gerais state confirmed there were dead and missing from the dam burst — but said it could not yet give a number.

Images from Globo TV showed the area of the operation overrun with water and clay-red mud, and large vehicles tossed on their sides.

A small cluster of homes and about 400 people live in the small town of Bento Rodrigues, about 7 kilometers (just over 4 miles) beneath the dam that burst. Images showed the town overrun with mud and water.

Authorities said the dam was built to hold back water and residue from mining operations, a mixture that can often be toxic.

The Samarco mining company said in a statement on its website that it was making "every effort to prioritize care to people and mitigate damage to the environment."

"It is not possible at this moment to confirm a cause ... nor if there are victims," it added.

Police, firefighters and city officials also said they could not confirm any victims.

A statement from the city hall of Mariana, a city of about 40,000 people 300 kilometers (185 miles) north of Rio de Janeiro, said the dam ruptured at 4:20 p.m. in an area roughly 20 kilometers (over 12 miles) from the city center.