The U.S. on Tuesday was dispatching disaster rescue teams to earthquake-stricken Haiti, where a U.S. official said a “serious loss of life” was expected.

President Barack Obama said his thoughts and prayers were with the people of Haiti and that the U.S. stood ready to help the impoverished Caribbean nation.

While telephone lines were down in the Haitian capital of Port-au-Prince and cell phone communication was spotty, U.S. officials there reported “significant damage.”

“There were some people  in the city when the earthquake first happened,” State Department spokesman P.J. Crowley said. “They reported structures down. They reported a lot of walls down. They did see a number of bodies in the street and on the sidewalk that had been hit by debris. So clearly, there’s going to be serious loss of life in this.”