A 56-year-old Navy Department engineer, variously described as mild-mannered and contentious, shot five of his Northeast Washington neighbors last night, one fatally, before killing himself with a.38-caliber revolver, D.C. police reported.

The engineer was identified as Carroll T. Fleet of 5608 First St. NE, a civil engineer who was a section head in the Naval Ship Engineering Center in Crystal City.

According to police and neighbors, he had been embroiled for some time with residents of his street in a series of disputes apparently exacerbated by an argument yesterday about automobile parking spaces and rights of way in the snow.

During a brief flurry of gunfire, in which Fleet apparently reloaded once and fired about a dozen shots, police said, he wounded Leroy Williams Sr. and Jr., who live across the street from Fleet, and Everette Davis Jr., who lives around the corner at 33 Madison St.

Marla Haney, 16, was critically wounded, and her mother, Betty Haney, 57, was killed in their house at 5607 First St., NE, police said.

After declaring, "Everybody's going to die today," Fleet shot himself and fell fatally wounded in the front upstairs bedroom of the Haney residence, police said. Yesterday was Fleet's birthday, they said.

Police said Fleet and the Williamses apparently had argued yesterday about the right of way on First Street where only one lane was cleared.

Police said the Williamses, who were accompanied by Davis, returned about 8 p.m. in their 1977 Buick from grocery shopping and were just leaving the car when Fleet approached and opened fire with the revolver.

The elder Williams was shot in the chest. His son was hit in the arm. Davis was struck beneath the chin. All three ran into the Williams house, police said.

After reloading, police said, Fleet went next door to the Haney residence, smashed the glass storm door and began pounding on the main door.

Mrs. Haney opened the door, was shot in the chest and was killed instantly, police said. She fell in the front hallway.

Then, police said, Fleet went upstairs and shot and killed the Haney family's black and white collie.

In the upstairs bedroom, authorities said, Maria Haney was shot once in the head and twice in the chest, while her 15-year-old sister, Kimberly, hid in a closet.

After shooting himself in the head, Fleet fell to the floor near the body of the wounded girl, officers said.

Police said they knew of no dispute between Fleet and the Haney family.

A supervisor in the Ship Engineering Center described Fleet's work as "very good." A colleague called him a "very mild-mannered person" and said, "I can't imagine him getting in an argument with anyone."