Baker, shown in a 1993 photo, is wanted for questioning.
SILVER SPRING, Md. -- Police linked the shooting of a 72-year-old man in Washington to the sniper killings of five Maryland residents and said that the same high-powered rifle was used to kill at least four of the victims.
Authorities were searching for two men, including one with North Carolina ties, for questioning, and were investigating whether a seventh shooting outside a Virginia store was part of the same crime spree.
Late Friday, federal authorities in Charlotte issued a bulletin for a 33-year-old former Raleigh man in connection with the shootings. Robert Gene Baker III was believed to be heading south from Washington and may have associates in Virginia and North Carolina, the Bureau of Alcohol, Tobacco and Firearms said.
Baker previously lived in an apartment at 9135 Stonehenge Drive in North Raleigh. It was not known when Baker last lived in Raleigh.
Baker's family members reported him missing Monday, according to the ATF report.
The bulletin described Baker as a drug user affiliated with various militia and white supremacist groups. He is 5-feet-9 and 165 pounds, with brown eyes, brown hair and tattoos on both arms and his back.
Police are looking for a white 2000 GMC van with dark lettering. The vehicle has a Maryland registration.
The ATF says it believes Baker is armed with a handgun and high-powered rifle and should be considered extremely dangerous.
Baker was arrested in 1993 in Raleigh on a fugitive warrant and also was charged with not wearing a seat belt and driving without a license, according to Wake County court records.
In Washington, police reported that the same weapon was used in Friday's slaying as in three of the five shootings in Maryland, said Special Agent Michael Bouchard of the Bureau of Alcohol, Tobacco and Firearms. Forensic testing was still under way in the two other Maryland shootings.
"We are on track to get him," said Charles Moose, the Montgomery County police chief, and a 1975 graduate of UNC-Chapel Hill. But few witnesses saw the killings, and no shell casings were found at the crime scenes.
In the latest case linked to the sniper fire, a 72-year-old man walking near the Montgomery County line on a main northern Washington street was shot once in the chest Thursday night. He fell dead, just a short drive from the Montgomery County locations where the first five victims were killed.
The shooting Friday, still under investigation for links to the sniper cases, was in Fredericksburg, Va., 50 miles to the south.
At the Spottsylvania Shopping Center, a woman was shot in the back and critically wounded Friday afternoon as she loaded packages into her car outside a Michaels arts and crafts store. The police said a gray car was seen speeding off afterward.
The ATF has received a bullet casing from that shooting, and will test it, Moose said.
The police, saying they were in the early stages of the investigation, said they saw no immediate connection except the seemingly random nature of the shootings. But they expressed interest in the coincidence that the very first Montgomery County incident on Wednesday night was a shot fired through the window of another Michaels store in Wheaton, Md. That shot barely missed a store clerk, the police said, while the rifleman's next five shots resulted in five fatalities. Those victims died in separate attacks Wednesday and Thursday as they went about routine outdoor activities, from mowing the grass to cleaning out a car.
Moose, the Montgomery County police chief, confirmed Friday morning that ballistic evidence showed that the victims most likely were shot by a sniper using high-intensity .223-caliber bullets of the sort used by rifle hunters and soldiers.
"They don't appear to be anyone's enemies, just random targets," said Moose, noting the victims were from a variety of ethnic backgrounds.
Detectives' confirmation of the stalker's marksmanship plus the possibility that the gunman might have widened his field and struck again intensified the anxiety spreading through Washington and surrounding suburbs in Maryland and Virginia.
"People were just out doing ordinary things, and people just decide to drive by and blow them away," said Connie Gray, 69, a Montgomery County resident shopping near where a woman was shot through the head on Thursday as she sat on a bench outside a post office. "That saddens me, and it angers me."
Detectives indicated that they had a continuing suspicion that the method used by the rifleman was to take aim from a distance while hidden inside such a truck, beyond sight of immediate witnesses, and to speed away with the spent cartridge evidence.
While stressing this as the police's best theoretical lead, Moose rejected speculation that more than one gunman might be involved. He also said the white-truck scenario was one of many that could emerge as detectives seek fresh evidence.
The deadliness of the gunman's intent was clear as a federal firearms expert explained that the .223 caliber bullet, while relatively small looking, was designed for high-velocity firing from an outsized cartridge packed with extra gunpowder.
The very idea that such high-intensity open-field weaponry was being brought to bear covertly on suburbanites chilled residents trying to go about their business.
"You're afraid standing here that somebody might come along and shoot you -- you know it's possible," said Loretta Betesch, 42, an insurance saleswoman, pausing in a grocery store parking lot in Wheaton, where the first victim was gunned down on Wednesday. "It could happen anywhere. It's very unnerving."