A motorcyclist struck two young boys walking home from a day-care center in Southeast Washington yesterday afternoon, critically injuring both, D.C. police said. Authorities were searching last night for the motorcyclist, who fled the scene.

The two boys, ages 4 and 5, were being escorted home by a caretaker when they were hit about 4:30 p.m. in the courtyard of Woodland Terrace, a 234-unit complex in the 2700 block of Langston Place SE, police said.

Paramedics revived one child at the scene, just feet away from a playground at the complex, and both were taken by helicopter to Children's Hospital, police said. The caretaker was not injured.

Residents said that dirt bikes, a type of small motorcycle, are a problem in the apartment complex, where riders often speed around the courtyard area. Rosandra M. Hickson, 36, said that a motorcyclist had been riding in the courtyard since about noon yesterday and that security workers at the complex apparently did nothing about it.

Immediately after the collision, Hickson said, she "looked out there and I said, 'What's out there? Oh, my God. That's somebody's babies.' "

"I started crying, because I can't even let my children out there to play" because the courtyard area can be unsafe and because of the motorcycles, she said.

Hickson said that her husband has told several motorcyclists not to ride in the courtyard and that they have moved to an alley.

A 37-year-old resident of the complex who spoke on the condition of anonymity said she saw a woman trying to push the two boys out of the way of the motorcyclist, who the resident said was speeding. Immediately after the incident, Hickson said, the woman was crying.

The other resident added that she was looking through her apartment window when the motorcyclist struck the boys and that the driver had been injured. "He was on the ground; he was hurt, too," she said. "He looked at them kids, and he kept walking."

Cmdr. Joel Maupin said that the motorcyclist was believed to be in his twenties and that he abandoned the red and white dirt bike about a block from the scene.

Resident Antwonette Fulmore said the bikers ride along the courtyard daily. "When I hear it, I look back. They're always going really fast," she said.

The 2700 block of Langston Place SE, about five blocks from the Oxon Hill area of Prince George's County, has been the scene of other recent tragedies.

In August 2003, a 23-year-old man was killed and six people were wounded in a drive-by shooting in what police said might have been a dispute between rival gangs. In February 2000, a 16-year-old who lived in the block was fatally shot in a Southeast Washington neighborhood about 2.5 miles away.

Staff writer Del Quentin Wilber contributed to this report.