Missing from flood after dam failure are unlikely to be found alive, Brazilian governor says

People remove mud from a damaged home in Barra Longa after a dam burst on Thursday in Minas Gerais state, Brazil, Saturday, Nov. 7, 2015. Brazilian searchers are looking for 23 people still listed as missing following the burst of two dams at an iron ore mine in a southeastern mountainous area. (AP Photo/Felipe Dana) (The Associated Press)

Rescue workers search for victims at the site where the town of Bento Rodrigues stood, after two dams burst on Thursday, in Minas Gerais state, Brazil, Sunday, Nov. 8, 2015. Brazilian rescuers are looking for people still listed as missing following the burst of two dams at an iron ore mine which sent viscous red mud, water and debris flooding into the town, flattening all but a handful of buildings and killing dozens. (AP Photo/Felipe Dana) (The Associated Press)

A dog is seen in a destroyed house at the town of Bento Rodrigues after two dams burst on Thursday, in Minas Gerais state, Brazil, Sunday, Nov. 8, 2015. Brazilian rescuers are looking for people still listed as missing following the burst of two dams at an iron ore mine which sent viscous red mud, water and debris flooding into the town, flattening all but a handful of buildings and killing dozens. (AP Photo/Felipe Dana) (The Associated Press)

The governor of the Brazilian state where a flood of mud and water submerged a village last week after two dams breached at a nearby iron ore mine says there is little hope of finding those missing.

Minas Gerais Gov. Fernando Pimentel says it is still not known what triggered Thursday's failure of dams at the Samarco mine.

Speaking at a Sunday news conference, Pimentel called the accident "a tragedy of great dimensions."

At least one person is confirmed dead and more than two dozen are thought to be missing, though the number remains in flux.

Local officials have said pockets of survivors may still be holed up in isolated areas.

Helicopter searches for survivors resumed Sunday morning despite rainy conditions that have hampered rescue efforts.