President Obama on Tuesday asked Americans to "send their thoughts and prayers" to those affected by the mudslide in Washington state.
At least 14 are dead and scores more missing after a hillside collapsed Saturday.
"We know that part of this tightly knit community has been lost."
Obama said he had spoken with Washington Gov. Jay Inslee (D) and signed an emergency declaration providing aid to the state. That will allow the Federal Emergency Management Agency to send equipment and resources to the town of Oso, about 55 miles north of Seattle.
"My administration is in contact with them on an ongoing basis," Obama said.
The massive mudslide left nearly a square mile of debris in its wake and knocked over more than 100 homes.