A man who reportedly held a handgun to a pregnant woman's head a week ago fired at least six shots at her yesterday evening, fatally injuring her and her near-term fetus and critically injuring a 3-year-old boy who was standing with her, authorities said.

A second woman was treated for a small leg wound after being struck by a bullet, possibly a ricochet.

D.C. police said the pregnant woman, the boy and a 27-year-old woman, all believed to be Southeast D.C. residents, were standing together in an entrance walkway in front of 2840 Robinson Place SE about 5:25 p.m. when they were shot by a gunman. Witnesses, including a woman who said the gunman had threatened the pregnant woman earlier, said the gunman then fled on foot.

No arrest had been made last night, police said.

All three victims were taken to Greater Southeast Community Hospital, where Ann Cahill, a hospital spokeswoman, said the pregnant woman was taken to surgery but was pronounced dead about 8 p.m.

She said the pregnant woman, estimated to be within six weeks of term, was shot at least twice in the abdomen and two slugs struck the fetus. Cahill said the woman also received wounds in the chest, neck and head. It was uncertain how many bullets caused the injuries.

An attempt was made to save the fetus, Cahill said, "but there was no fetal heart beat when the woman was brought in." Cahill said the woman was "bleeding profusely when she came in," making it difficult for the emergency staff to determine the source of the bleeding.

The 3-year-old, identified by police as Marquis Shaw of 1626 R St. SE, was shot twice in the left abdomen, Cahill said. After the child's vital signs were stabilized at Greater Southeast, he was taken to Children's Hospital.

The boy was in critical condition after surgery, hospital spokeswoman Susan Zox said early today.

A woman who lives at 2842 Robinson Place, which is attached to 2840, said the pregnant woman recently had been confronted in front of the building by the same gunman.

The witness, who asked to not be identified, said, "Two weeks ago that same man came up to her and put a gun to her head and clicked the gun and it didn't go off . . . . The same lady."

Police sources confirmed that there is a police report of the woman being confronted in front of the apartment building by a man who produced a handgun.

Two years ago, two women and two men were found shot to death in an apartment at 2839 Robinson Place, one of a cluster of apartment buildings across from the scene of yesterday's shootings. Those slayings are unsolved.

Last night, several area residents said they suspected that yesterday's shootings were drug related.

Ronnie Faison, 21, who said that his cousin witnessed the earlier incident involving the pregnant woman, said that another of his cousins was one of the four persons killed two years ago across the street because he "was in the wrong place at the wrong time."

"It's these drugs," Faison said. "I'm not saying it's every day," he said of drug-related violence, "but you never know when it'll break out."