All five of them were doing the most ordinary things before a gunman ended their lives, one at a time, over 16 hours.

James Martin was in a grocery store parking lot on his way home from work.

Sonny Buchanan was mowing the lawn outside a car dealership.

Premkumar Walekar was pumping gas into his taxicab.

Sarah Ramos was sitting on a bench, waiting for her boss.

Lori Ann Lewis-Rivera was cleaning her minivan.

Last night, the police effort by dozens of local agencies had identified few threads to tie the victims of a proficient gunman whose targets crossed lines of culture and class.

One was black, one was Hispanic, one was Indian, two were white. Their ages ranged from 25 to 55. One was on foot, another tending to a well-kept vehicle.

How the killer chose his targets is a mystery. All Montgomery County Police Capt. Nancy Demme could say was that the victims "are across the board in gender and ethnic backgrounds."

James D. Martin

James D. Martin was heading home about 6 p.m. Wednesday to the Stonegate neighborhood in Silver Spring when he stopped at the Shoppers Food Warehouse on Randolph Road in Wheaton. Within moments, Martin, 55, had been shot, the 21st person killed in Montgomery County this year.

Last night, friends and family members clustered outside the home he shared with his wife and young son, a two-story house with light-green siding and blue shutters in the 15200 block of Centergate Drive near Colesville. Neighbor Ruth Dalton remembered Martin as the kind of neighbor who would be missed - especially at Halloween.

"He was extraordinarily friendly from the time he moved in," she said. When trick-or-treaters called, he was known for "making a big fuss over them."

'Sonny' Buchanan

James L. Buchanan Jr., 39, had no children of his own.

But for nearly a decade, Sonny, as he was known, served on the regional board of the Boys and Girls of Greater Washington. He volunteered with the county's Crime Solvers hot line. He doted on his two nieces and two nephews and a great-niece who turns 1 next week.

"He took a great interest in the kids of this county," said Tim Sheehan, executive vice president of the Boy and Girls Club of Greater Washington.

A classmate from Gaithersburg High School, Janice Kidwell, said those priorities never wavered.

"Family meant the world to him and he had a real commitment to community," she said.