The body of a 54-year-old Washington woman who had been stabbed six times was discovered by her son Tuesday evening less than three blocks from where Mayor Marion Barry was promoting his anticrime programs.

D.C. police said the body of Mattie Pope was found about 8 p.m. in the bedroom of her home at 645 14th St. NE. The D.C. medical examiner said Pope died of stab wounds to the chest and abdomen.

Police said there was no evidence of forced entry and nothing was missing from the two-story row house Pope shared with her son, Henry, and at least one other person.

At the time the body was found, Barry, who lived in the neighborhood until early 1980, was talking to residents about crime reduction while campaigning for reelection.

Robert Jacobs of 1378 F St. NE said that about 8 p.m. he was among a crowd of people talking to the mayor near 14th and F streets NE.

" . . . finding this lady's body right around the corner from where the mayor was talking underscores the crime situation in D.C. People aren't even safe in their own homes," said Jacobs, an employe of the State Department.

A spokesman for Barry said the mayor was unaware of the crime. D.C. homicide detectives said that they have no motive and no suspects in the stabbing.

In an unrelated homicide Tuesday night, the body of 47-year-old Richard Petty was found in an alley alongside a vacant lot in the 2100 block of Eighth Street NW, police said. Petty had been stabbed several times in the body.

Police said that Petty was known as a "street person" who often slept in the lot.

In another unrelated incident, police reported that a 22-year-old Northwest man was shot during a street fight early Wednesday in the 300 block of Elm Street NE.

Clifford Talley of the 1200 block of North Capitol Street was taken to Washington Hospital Center after being shot several times in the body and once in the eye. He died there later.

Witnesses told police that three men were involved in the fight, which broke out around 1 a.m.

Police said yesterday evening that they have a suspect in the shooting.