WASHINGTON (AP) - The only predictable thing about the elusive sniper - or snipers - terrorizing the Washington area is the unpredictability of the crimes.

The 11 apparently random victims were male and female; old and young; black, white, Hispanic and Asian. The shootings have occurred in the morning and at night. Four were at gas stations, but the crime scenes also have included a sidewalk bench outside a post office and strip mall parking lots.

Experts say the killer, or killers, appear to be thrill-seekers who revel in the fear they’ve created and the attention the crimes are receiving.

Scott Thornsley, a criminal justice scholar at Mansfield University, who specializes in serial killers, said the shooter may be planning how to increase the thrill level of his next attack. The most recent confirmed victim, Thornsley pointed out, was killed across the street from a Virginia state trooper.

“He’s operating on his own timetable. He can choose the place, the time, the location, the number of witnesses,” Thornsley said. “He is absolutely dictating the pace of the investigation, in a sense, by shooting so many people in a short period of time. He’s driving the police crazy.”

The 11th victim was shot Monday night at a parking lot in northern Virginia, near the intersection of several major thoroughfares.

Clint Van Zandt, a former FBI profiler, said the location of the latest killing _ in a highly congested area _ sets the slaying apart from the others. “This is not bold, this is brazen,” he said.

Sniper fire has cut down nine people and wounded two since the killing started the night of Oct. 2. Another attack occurred Monday night when a woman was shot dead outside a Home Depot store in Falls Church, Va., about 10 miles west of Washington.

Fairfax County Police Chief Tom Manger said Tuesday that ballistic evidence conclusively linked the shooting to other sniper attacks in the Washington area.