The official death toll from a huge US landslide rose to 34 on Tuesday as the White House announced that President Barack Obama will visit the scene later this month.

Up to 12 people are still believed missing after a wall of mud and debris crashed down on the small town of Oso in the forests of Washington state on March 22.

Of the 34 bodies recovered, 30 have been identified, according to the Snohomish County Medical Examiner's Office.

The dead include a four-month-old baby girl, as well as a a five-year-old girl, a six-year-old boy and a 13-year-old boy, it said.

In Washington, White House spokesman Jay Carney said Obama will travel to Oso on April 22 to "to view the devastation ... and meet with the families affected by this disaster, as well as first responders and recovery workers."

Dozens of dwellings in the rural town 60 miles (95 kilometers) from Seattle were wiped out in the landslide, which also destroyed part of a highway.

The county sheriff's office said Monday that 12 people remain missing. There was no immediate update on the missing Tuesday.

The White House spokesman added: "Our thoughts and prayers go out to everyone who lost a loved one. The administration remains focused on supporting state and local efforts and first responders."