A speeding car passed a sentry post at the front of the U.S. Capitol Building early yesterday, went across the parking plaza and hit a retaining wall, then shot through the air across Constitution Avenue and crashed into two trees in Senate Park, police reported.

"After a preliminary investigation, we have no reason to believe this was other than a traffic accident," said U.S. Capitol Police spokesman Jeffrey Zanotti.

Inspector Bob Howe said that no weapons or explosives were found in the car. He said that the driver, Rodney Parker, 30, of 2403 Southern Blvd., Temple Hills, was charged with driving under the influence, speeding and reckless driving.

Parker, a security guard for the Smithsonian Institution, was listed in critical condition last night after 14 hours in surgery. A hospital official said Parker sustained massive head injuries.

A passenger, Reginald Adkins, 27, of 2625 Martin Luther King Ave. SE, was treated for minor injuries at Capitol Hill Hospital and released, the hospital reported.

Zanotti said the car was headed north on New Jersey Avenue SE about 6:30 a.m. when it failed to stop at a traffic light at Independence Avenue on the south side of the Capitol grounds and raced past a security post into the parking plaza on the east front of the building.

The car, traveling at more than 60 mph, raced across the parking lot and, as it approached a barricade on the north side, it veered to the left, jumped a curb and sped across a small patch of grass to a retaining wall that runs parallel to Constitution Avenue NW, he said.

The car hit the wall, sailed over a car on Constitution Avenue to the far side of the street, jumped another curb and hit a tree in Senate Park.