(Updated at 11:10 a.m. ET)
Washington (CNN) - President Barack Obama pledged Wednesday that the U.S. government would lead "a swift, coordinated and aggressive effort to save lives" in Haiti after that country's powerful 7.0-magnitude earthquake.
Obama said U.S. relief efforts would be coordinated by the administrator of the U.S. Agency for International Development, Dr. Raj Shah.
He urged Americans trying to locate family members in Haiti to contact the State Department at phone number 888-407-4747.
"The reports and images that we've seen of collapsed hospitals, crumbled homes and men and women carrying their injured neighbors through the streets are truly heart-wrenching," the president said at the White House.
"For a country and a people who are no strangers to hardship and suffering, this tragedy seems especially cruel and incomprehensible."
Obama said U.S. relief efforts are currently focused on a quick accounting of U.S. embassy
personnel and their families in Port-au-Prince, as well as other American citizens living and working in Haiti.
The president noted that "military overflights have assessed the damage" from the earthquake and that civilian disaster assistance team were beginning to arrive in Haiti.
Search and rescue teams from Florida, Virginia and California will arrive on Wednesday and Thursday, he added.
"Because in disasters such as this the first hours and days are absolutely critical to saving lives and avoiding even greater tragedy, I have directed my teams to be as forward-leaning as possible in getting the help on the ground and coordinating with our international partners," he said.
Obama received two memorandums updating him on the situation in Haiti early Wednesday morning, White House spokesman Tommy Vietor said. One of the memos, from the president's national security adviser, described "key decisions that have been made, and actions that have already been taken."
Obama also received an additional update from his national security staff Wednesday morning, Vietor added.