A woman was shot to death yesterday as she was leaving work at a Capitol Heights grocery store, and her apparent assailant--identified as her estranged husband--then turned the gun on himself, Prince George's County police said.

The man died later at Prince George's Hospital Center.

Police, who described the shootings as apparently murder and suicide, identifed the dead as Wannetta Carole Medley, 45, of Clinton and Izel Medley Jr., 56, of Landover. Investigators said the couple had a history of domestic disputes.

Wannetta Medley was shot once in her left side as she sat in the driver's seat of her car in the parking lot of the Coral Hills Shopping Center at 4801 Marlboro Pike, police said.

Investigators said her estranged husband then fired a bullet into his head as he stood next to her brown Pontiac Parisienne. He collapsed onto the pavement, but was still alive when police arrived about 3:20 p.m.

The couple had been separated for some time, according to Deborah Palmer Mackall, Wannetta Medley's sister-in-law.

Police said they recovered a .25 caliber semiautomatic pistol a few feet from the man's body. They also said they had not ruled out the possibility that someone else may have been involved in the incident.

Co-workers and relatives said Wannetta Medley had worked as a produce clerk for Shoppers Food Warehouse for about a dozen years and that she had just finished her afternoon shift when she was killed.

"She was a quiet person, but she always spoke with a smile," said Sandra Forrest, a fellow employee at the grocery store. "She didn't talk much, but she was a very nice person, a child of God. It's sad, really sad."

The shooting attracted scores of onlookers to the bustling shopping center parking lot, which attracts patrons from Capitol Heights as well as nearby neighborhoods in the District. A crowd gathered around the spot where Medley was slain, a parking space next to the drive-through window of Mickey's Subs Shop, directly under a large red sign advertising the restaurant's "World Famous Buffalo Wings."

"It's frightening," said Helen Lattisaw Gibson, a District resident who comes to the store to shop three times a week. "My heart is beating a hundred miles an hour. This is the first time I've ever seen anything like this happen around here."

CAPTION: A police officer looks inside the car in the 4800 block of Marlboro Pike where Wannetta Carole Medley was killed.