A 66-year-old pastor who also worked in the construction business was fatally shot early yesterday as he pumped gas in Northeast Washington, police said.

Fletcher M. Lyles was standing next to his pickup truck about 4:40 a.m. at a Citgo gas station in the 3800 block of Minnesota Avenue NE when a gunman approached and opened fire, police said. He was struck in the chest and leg and died about an hour later at Prince George's Hospital Center.

Detectives are examining the possibility that Lyles was the victim of a failed robbery attempt or was shot in retaliation for an earlier argument or incident, police said. Carjacking does not appear to be a motive, because the assailant did not get into Lyles's pickup, according to investigators.

Police said they impounded a red Nissan that did not have any tags near the gas station. Several men were seen standing at the car when the shooting occurred, police said.

Detectives planned to revisit the gas station early today to question people who might have been in the area at the time of the shooting, police said.

"Right now, we're talking to some people, but we don't know the motive," said Lt. William Farr of the D.C. police violent crimes unit, who expressed frustration at the difficulty in finding witnesses to aid in the investigation.

Lyles was probably heading to his job as a supervisor at a construction site in the District when he was pumping gas. Investigators and relatives said they did not know what company employed him or where the job was.

He was pastor of Mount Zion True Grace Church of Christ, which is housed in a small storefront building in the 2200 block of Minnesota Avenue SE. He lived in that block, police said.

Family members said Lyles was a quiet man who mostly kept to himself and was devoted to his children. He was known for keeping a Bible close at hand, they said.

"His hobby was being with the Lord," said one of his sons, Isaiah Lyles, 23. "He was a good father and husband."

Lyles, who had eight or nine children, had been a pastor for several years at the church and had a loyal congregation, Isaiah Lyles said.

Police urged anyone with information to call detectives at 202-727-9099. D.C. police offer rewards of as much as $25,000 for information that solves homicide cases.