WASHINGTON (CNN) -- U.S. Defense Secretary Robert Gates suffered a fractured shoulder after slipping on ice Tuesday night at his Washington home, the Pentagon said.

Gates, 64, didn't seek treatment until Wednesday morning when he checked into Walter Reed Army Medical Center, said Pentagon spokesman Geoff Morrell.

"I think he's in a lot of pain," Morrell said.

Gates apparently slipped as he returned from dinner, he said.

Gates will continue to perform his duties as defense chief, Pentagon officials said.

Gates won't be able to appear Wednesday for a hearing on the Pentagon's budget before the House Appropriations Committee. Deputy Defense Secretary Gordon England will testify in his place.

A ice storm hit the Washington area Tuesday, snarling traffic and preventing some voters from casting ballots in the presidential primaries in the District of Columbia, Virginia and Maryland.