A 72-year-old pedestrian shot to death Thursday night on a District street corner was killed by the same gun used in at least three of five fatal shootings hours earlier in Montgomery County, police said last night. They said they were also trying to determine whether a woman shot yesterday in the parking lot of a Virginia shopping mall was a victim of the same elusive assailant.

"Whoever is involved in this madness, rethink what you're doing," Montgomery Police Chief Charles A. Moose said last night, speaking at a news conference. "Turn yourself in. Surrender to law enforcement."

Meanwhile, a North Carolina State Highway Patrol communications supervisor said his agency, after receiving information from the federal Bureau of Alcohol, Tobacco and Firearms, began late last night to broadcast a lookout for a man who is wanted for questioning in the shootings. The supervisor said the man was not described as a suspect.

The Raleigh News & Observer said a bulletin from the ATF said the man had once lived in North Carolina and had been affiliated with militia and white supremacist groups.

The ballistics tests reported last night established the connection between the District shooting and three of the Thursday morning attacks in Montgomery. Authorities said it may not be possible to reach the same conclusion about the bullet fragments from the other two Montgomery attacks because of the poor condition of those bullets.

However, Moose said, "It would be very strange if the other two didn't match."

Police said ballistics tests showed that the weapon that killed Pascal Charlot as he stood at Kalmia Road and Georgia Avenue NW late Thursday was used in a series of apparently indiscriminate attacks that terrorized a swath of Montgomery County. In the Montgomery shootings, a man was gunned down outside a supermarket Wednesday night; then two men and two women were slain Thursday morning in separate attacks in a little more than two hours.

Last night's announcement came as authorities investigated the possibility that the shooting outside a shopping mall in Spotsylvania County was also linked to the Montgomery attacks.

The Virginia attack occurred at 2:30 p.m. yesterday at the Spotsylvania Mall, where a 43-year-old woman was shot in the back and seriously wounded while loading packages into her minivan outside a Michaels craft store, authorities said. The woman, whom police did not identify, was in serious condition last night at Inova Fairfax Hospital.

It was another instance of a person going about an ordinary chore, gunned down by an assailant who may have fired from a distance, and vanished like a ghost. Moreover, the Virginia shooting occurred outside a Michaels store. Authorities believe the deadly Montgomery attacks were preceded by a shot fired Wednesday night into a Michaels store in Aspen Hill that did not hit anybody.

In the District attack, Charlot, who lived in the Petworth section of Northwest Washington, was fatally shot in the chest about 9:20 p.m. Thursday while standing in a commercial strip a half-block from the Montgomery border.

One witness to the District shooting said he heard a single shot; the sound of a single shot was heard at the county shootings as well.

D.C. Council member Adrian Fenty (D-Ward 4) warned that District residents should pay attention to alerts issued in Montgomery. "These people are not paying attention to state lines," he said of the assailants.

Special Agent Michael Bouchard of the Bureau of Alcohol, Tobacco and Firearms said that only four of the bullets could be positively linked to the same gun because "in some cases, the condition of the projectiles [is] not as good as . . . in some of the other ones."

In the Montgomery slayings, one of the victims was vacuuming her minivan at a Shell gas station in Kensington; one was pumping gas at a Mobil station in Aspen Hill; one was in the parking lot of a grocery store in Glenmont; one was pushing a lawn mower near Rockville Pike; and one was sitting on a bench near the Leisure World retirement community in Silver Spring. No witnesses reported seeing the shots fired.

Yesterday, as the probe widened, Montgomery County Executive Douglas M. Duncan said police had developed hundreds of credible leads and were "tracking every piece of information we get."

"We're conducting a massive investigation, a massive manhunt, to bring this person to justice," Duncan said.

The FBI was developing a psychological profile of the killer, which officials expected to deliver to Montgomery police today. And investigators continued to search for a white "box truck" that a witness reported seeing speed away from one of the shooting scenes on Thursday. Police also said that autopsies on the five Montgomery victims had been completed but that written reports were not yet available.

Moose said last night that microscopic comparisons have linked the .223-caliber rounds from the killings at the Shell and Mobil stations and near Leisure World. He said that "the work just hasn't been done" in a ballistics laboratory that could connect bullets used in the other two Montgomery killings.

D.C. Police Chief Charles H. Ramsey said yesterday that medical examiners had pulled numerous bullet fragments from Charlot's body during his autopsy. A D.C. police department source said that the bullet probably was fired from a distance.

In Virginia, the shot that wounded the woman went through the lower right side of her back and exited under her left breast, lodging in the back of her minivan. It was not clear last night whether that slug was in a condition to be tested.

Moose called the investigation "one of the most complex cases I've been involved with." As for the killer or killers, he said, "it could be military, it could be a hunter, it could be someone . . . who has interest in weapons.

"We're operating under the pretense that they are still in the area," he said. "We owe that to the people who live here."

Speaking to reporters yesterday, Moose urged that the public be patient. He said that "in terms of the suspects, we are certainly not closing any door. We are taking a broad-brush approach to this. We don't have enough information at this point to narrow it down and eliminate anyone."

As for whether the attacks could be the work of a terrorist group, Moose reiterated: "We are not closing any avenues. We are a large suburban community adjacent to the nation's capital. We understand what that may mean to people that may be looking to make a point."

Police said the District crime scene -- an open intersection surrounded by low buildings housing carryout restaurants, nail shops and a laundromat -- was quiet before the shooting, with only a few cars waiting at a red light. Most witnesses reported hearing one shot, then seeing Charlot crumple.

Some reported hearing a second shot, police said, but that sound might have been an echo of the first shot. No one reported seeing a gunman, police said.

In Spotsylvania yesterday, sheriff's deputies and federal agents were combing the mall's sprawling parking lot. "We have no leads. We have no witnesses," said Maj. Howard Smith of the Spotsylvania County sheriff's department. "At this point we have no one who saw anything."

Smith said investigators have recovered evidence but would not say what it was. It was turned over to ATF last night for testing, he said, adding that investigators don't know yet what kind of gun was used in the shooting.

Investigators in Maryland visited gun stores yesterday in search of leads.

John Schelin, owner of Schelin's Gun Shop in College Park, said that the .223-caliber bullet is very popular and is used often for target shooting and competitions. "The U.S. Olympic team uses .223-caliber shells," he said.

Montgomery police, who set up a special tip line, said they were receiving more than three times as many calls as usual from people with tips. At least two times yesterday the deluge of calls overloaded the tip line, and some callers were unable to get through. Police officials said that by yesterday afternoon they had fixed the problem and urged callers to try again.

"We wish that in 2002 our technology would support our ability to take phone calls, but it has not," said Lucille Baur, a police spokeswoman.

The number of calls spiked yesterday afternoon after descriptions of possible weapons used in the shootings were released to the media. Officers trained in investigations are taking all the calls, documenting credible information and forwarding tips on to superiors who have dispatched patrol officers and detectives to investigate, police officials said.

"If we receive information that appears to be credible, then we will follow up on it," Baur said.

The tip line was initiated after the county's 911 system and the department's general number were inundated with calls about the shootings. Many tipsters told police about sightings of white box trucks and of hearing the sound of gunshots in the area of the shootings, officials said.

The location of the investigators taking the calls has been changed at least twice, officials said. At one point the call takers were in the major crimes unit and were surrounded by photos and drawings of the shooting scenes and possible evidence, officials said. The location has since been moved, but police would not say where.

Although police would not say how much of their evidence has come from the calls, they said the tips would be crucial to solving the case.

"Our belief is that there are people out there, certainly more than one, who know about the shootings," Baur said. "We have pieces of a puzzle, and the more pieces we have, the better."