In the nation's second workplace mass shooting in a week, a man opened fire yesterday morning at two companies in a Birmingham suburb, killing three people.

The suspect, who had worked at both of the Pelham, Ala., firms, was arrested after scuffling with officers who had forced his vehicle to the shoulder of Interstate 65 in nearby Chilton County, following a brief chase. He was identified as Alan Eugene Miller, 34, of Billingsley, Ala., a rural community about 50 miles south of Pelham, and charged with three counts of capital murder.

The latest shootings came one week after disturbed stock trader Mark O. Barton went on a shooting rampage in Atlanta on July 29 that left nine people dead and 13 wounded at two day-trading firms. Barton, 44, who killed himself later that night, already had slain his wife and two children from a previous marriage.

In the shootings in Pelham, a middle-class town of 9,000 south of Birmingham, police said the motive was unclear. They also would not specify the type of handgun used; it was recovered on the seat of the suspect's vehicle.

Although police would not speculate whether the latest tragedy had been inspired by the Atlanta rampage, it was similar in that it involved two separate workplaces, with the shooting at the second occurring even as police were responding to the shooting at the first. Pelham is about 150 miles west of Atlanta.

At 7 a.m. yesterday, Pelham police received a call about a shooting at Ferguson Enterprises, a company that distributes wholesale plumbing, heating and air conditioning equipment. The suspect was an employee, Chief Allan Wade said.

Two Ferguson employees, later identified as Lee Holbrooks, 32, of Pelham, and Christopher Yancy, 28, of Alabaster, Ala., were found fatally shot there.

As police were securing that scene, a second 911 call came in reporting a shooting at Post Airgas, a company that sells oxygen and other gases to hospitals. The suspect had previously worked at the firm, police said. There, police found a third victim, identified as Terry Jarvis, 39, of Montevallo, Ala.

Little information was released about the suspect. His mother, Barbara Miller, with whom he lived, said she had noticed nothing amiss when he left for work yesterday morning. He "went off to work just as he always does . . . . He left here like he always does, with a 7-Up and a couple of things of biscuits and sausage," Barbara Miller told the Associated Press. "Alan didn't bother anybody."

Neighbor Wayne Miller, no relation, said he had been impressed by Alan Miller's friendliness when he talked to him once before.

"I was putting in some posts along a fence a while back, and he just stopped this little small pickup truck he had and introduced himself," Wayne Miller said. "He mentioned the fact that my name's Miller also, and kind of laughed about that. He said he worked near Birmingham and drove nearly 100 miles every day just to get there."

Wayne Miller said he did not know whether Alan Miller was married or had children. He said the suspect lived about a quarter-mile from him, in a mobile home.

Don Blankenship, a spokesman at Ferguson Enterprises' corporate headquarters in Newport News, Va., said the company would release no information yesterday on the suspect or the victims.

"We are deeply saddened by this act of senseless violence," Blankenship read from a prepared statement. "We are greatly appreciative of the support and assistance we have received from the police and the community. Our prayers and condolences are with the families of the victims. Our focus today is to do all that we can to support the families of our slain associates and our other associates at that location."

In Pelham, businesswoman Aeta Hwang said that her customers at Pelham Cleaners were aghast at the latest tragedy involving an enraged worker opening fire on the job. She described Pelham as a bedroom community to Birmingham, with most people working in the city and opting to live in this peaceful community of farmlands and new shopping centers.

"We were all wanting to say that it couldn't happen here, but it is terrible nowadays--no place is safe anymore," Hwang said. "Everybody can own guns and go shooting."