A 21-year-old Capitol Heights man was shot and critically wounded by two plainclothes Prince George's County police officers who were chasing him last night when he reached into the waist of his pants as if he had a weapon, officials said.

They said the wounded man, identified as Ronald Walker of 5711 Coolidge St., was struck by an undetermined number of shots. Walker was a suspect in what the officers believed was a drug transaction on Maryland Park Drive in Capitol Heights about 6 p.m.

Police spokesman Cpl. Bruce Gentile said the officers, Cpl. Steven F. Kane, 32, and Pfc. Purcell O. Alston Jr., 24, saw an apparent drug deal while sitting in a car nearby. He said that when the officers approached the suspect and identified themselves, the man fled.

The two officers chased the man briefly, Gentile said, and after he refused their orders to stop, the man appeared to reach into the waistband of his pants. Gentile said the officers, "fearing for their safety," then fired several shots.

After the shooting, a knife and several bags of substance believed to be marijuana were found near the man, Gentile said.

Walker was taken to the Prince George's General Hospital, where he was listed in critical condition last night.

The officers were placed on routine administrative leave pending the completion of an investigation, Gentile said.