The state medical examiner's office has revised the death toll from a tornado in an Oklahoma City suburb to 24 people, including seven children.
Spokeswoman Amy Elliot said Tuesday morning that she believes some victims were counted twice in the early chaos of the storm. Authorities said initially that as many as 51 people were dead, including 20 children.
Teams are continuing to search the rubble in Moore, 10 miles south of Oklahoma City, after the Monday afternoon tornado.
Monday night, President Obama declared it a major disaster area.
Meanwhile, officials at two hospitals say they're treating more than 140 patients, including about 70 children.
The OU Medical Center says its treating about 85 patients, including 65 children. Their conditions range from minor injuries to critical.
Integris Southwest Medical Center says nine of 57 patients being treated at that facility are listed in critical condition. Nineteen are in serious condition and 29 others are listed in fair or good condition.
Five of the patients were children who have since been treated and released.
President Obama ordered federal aid to supplement state and local recovery efforts. Individuals and business owners affected by the disaster may apply for federal grants for temporary housing and home repairs, low-cost loans to cover uninsured property losses and other programs.
The president promised federal assistance in a phone conversation earlier Monday with Oklahoma Gov. Mary Fallin.
The Federal Emergency Management Agency has sent a special team to Oklahoma's emergency operations center to help out and dispatch resources.
Officials in Joplin, Mo., have brought together a team of public safety employees they are sending to tornado-stricken Moore.
Joplin was devastated by a tornado two years ago that killed 158 people and injured hundreds more.
On Monday, Joplin organized a team of about a dozen police and firefighters to assist in Moore.
Joplin City Manager Mark Rohr says his community remembers the assistance it received in 2011 and feels an obligation to lend a hand in Moore.