Two young men and two juveniles, all of them convicted felons, overpowered a worker at the District's Oak Hill juvenile detention facility in Laurel last night and escaped, officials said.

The breakout occurred shortly before 9 p.m., said Robert Little, youth services administrator for the Department of Human Services. DHS oversees the Oak Hill facility, where District youths convicted of serious crimes are held.

According to Little, the four escapees overpowered the employee, shoved him into a room, took his keys and opened a back door. They then escaped through the 14-foot barbed-wire fence that surrounds the facility, he said.

The employee was shaken but not injured, Little said. Employees at Oak Hill are unarmed.

The escapees were not identified, and it could not be learned what they had been convicted of.

Officials from Oak Hill, the U.S. Park Police and the Laurel Police Department were searching for the four late last night.

Officer Gene Windsor of the Park Police said units patrolling the nearby Baltimore-Washington Parkway also were alerted. "Escapees usually head right straight for their home," Windsor said.

Escapes have been an ongoing problem at Oak Hill.

In June, 17 youths fled the facility. Little said at the time that a chronic shortage of guards was at least partly responsible for the breakout. In 1988 and 1989, a total of 128 youths escaped from the facility.

"Obviously, I'm not pleased any time any of these situations occur," Little said last night, adding that changes would be made at the facility if an investigation indicated they were necessary.