To the three children, Monday evening's outing was a shopping trip to buy crayons, an art smock and other supplies for the new school year. But a half-hour later, the trip to Essex ended, when Mark Alen Clark, 32, detonated a bomb, killing himself, his estranged wife and the children.
Yesterday, as federal agents and Baltimore County police reconstructed the bombing -- and the lives of the victims -- they said that the device Mr. Clark used was a powerful explosive regulated by the federal and state governments.
Investigators were focusing on several types of commercial explosives commonly used by construction and mining companies, said Cliff Lund Sr., an explosives enforcement officer with the Bureau of Alcohol, Tobacco and Firearms. His assessment was confirmed by two county police bomb technicians.
Killed in the blast were Mr. Clark, his estranged wife Betty Louise Clark, 32, of the 6700 block of Havenoak Road in Rosedale; the couple's 4-year-old daughter Krysta of the same address; and Ricardo Valdez, 6, and Malissa Ray, 11, Mrs. Clark's children from previous relationships.
"He took my sister," Katherine Weber, 35, said, sobbing. "He took them all."
Mr. Clark drove the victims to an alley behind the Middlesex Shopping Center in the 1200 block of Eastern Blvd. and detonated the powerful blast that scattered pieces of his 1987 Ford station wagon -- and body parts -- hundreds of yards away.
Acquaintances and officials drew a harsh portrait of Mr. Clark, describing him as a brash bully. His wife, they said, had come to the Baltimore area this year to escape abuse at his hands.
"He was a wacky person," said Mrs. Clark's brother, Ronald Twoey, 37, of Pikesville.
"People viewed Clark pretty much as a bum," added Capt. Brian Uppercue, a county police spokesman. "He never held a job for an appreciable amount of time, abused his wife and kids and traumatized an entire community."
Ms. Weber said that a year ago, Mr. Clark put a gun to his wife's head and threatened to kill her. Although she was not aware of Mr. Clark ever hitting her sister, he would often threaten her life in front of the children, she said.
Mrs. Clark never called the police or filed for restraining orders against her husband, Ms. Weber said.
Mrs. Clark separated from her husband this summer and moved in with Ms. Weber for about a month to escape the abuse. Mrs. Clark was desperate to start a new life away from the troubled one she shared for six years with Mr. Clark in Cumberland, her sister said.
Family members said Mrs. Clark dreamed of becoming a medical secretary and recently enrolled in a job training program in Essex. Monday was her first day.
"She was just getting on her feet," Ms. Weber said quietly.
Ms. Weber said she saw a television report Monday night about the bombing and immediately began to suspect what her brother-in-law had done. Last weekend, Mr. Clark had said he was going to "blow himself away," she said.
But he often exaggerated, she said. "Obviously, he meant it this time."
Michael Albert, Ms. Weber's boyfriend, said he told police that Mr. Clark showed him what appeared to be sticks of dynamite in the trunk of his car Saturday.
"He said he was thinking about ending it, but with that guy, when he said something it was in one ear and out the other," Mr. Albert said.
ATF spokesman Roy Cheeks said the bureau was investigating whether the materials in the car were the actual explosives used.
Mrs. Clark's boyfriend, Mark Weitzel, said he moved into a two-bedroom apartment on Havenoak Road with her and the children in July. It was there that Mr. Clark picked the family up Monday.
"He picked them up around 5:30 p.m. and between 6 and 7 he blew them up," Mr. Weitzel said, shaking his head. "I'm sitting here right now waiting to wake up from this dream."
Mr. Weitzel said he was watching a football game when a report came on about the bombing. Because the initial bulletin said a minivan was destroyed, and Mr. Clark had been driving a station wagon, Mr. Weitzel said he gave it little thought.
"Forty-five minutes later the ATF was knocking on my door," Mr. Weitzel said. "I looked at [an agent's] jacket and back at my TV and I lost it."
Mr. Clark had no record of criminal violations in Maryland, police said. Federal authorities said, however, that he had been arrested in a theft case in 1980 in Missouri and on suspicion of passing bad checks in Keyser, W.Va., five years ago.
Mrs. Clark's brother complained that Mr. Clark moved from job to job -- as many as 20 in the past five years -- bullied Mrs. Clark and "whipped" the three children. That, said Mr. Twoey, led to more than one confrontation with his brother-in-law.
He remembers telling Mr. Clark a couple of years ago, "I'll kill you with my bare hands if you don't leave her and her kids alone."
Mr. Clark continued to harass his wife even after she moved to suburban Baltimore, Mr. Twoey said. He said he drove from his Pikesville home to Cumberland a couple of months ago to confront him. As in previous confrontations, Mr. Clark seemed oddly nonplused, saying little, Mr. Twoey said.
Meanwhile, classmates of the young victims were learning to deal with the horror of losing them to violence.
Malissa Ray was a seventh-grader at Golden Ring Middle School in the 6700 block of Kenwood Ave. Principal Bronda Mills said Malissa's transcript from the Garrett County school she had attended included these comments: good student, enjoyed having her in class.
One of Baltimore County's crisis teams will be at the school today. Ms. Mills was to have an emergency faculty meeting, prepare a statement to be read to the students and send a letter home and "make sure that the ones hearing this will have a way of expressing their feelings."
At Shady Spring Elementary School, 8868 Goldenwood Road in Rosedale, where Krysta and Ricardo attended, principal Gary W. Hilleary said, "We're very concerned about the students' feelings. . . We're all very saddened."
Friends and family described Betty Clark as a generous woman who doted on her children, often taking them out to play or swimming.
"Betty was an easygoing, friendly person who would do anything for you," said Mary Thomas, an upstairs neighbor of Ms. Weber's. "Those kids were everything to her."
Ms. Thomas said the children spent part of the weekend with their aunt, playing outside with neighborhood children and visiting their cousins. Ricky loved to hunt for frogs behind his aunt's house. Krysta was excited about her first full week of preschool. Malissa, blossoming into a young lady, still loved to frolic with her siblings. The night before they were killed, the children slowed down long enough to enjoy end-of-summer banana splits.
"Ricky spilled chocolate right here," neighbor Pam Pierce said, pointing to a spot of the steps of the apartment building. "We'll never wash that off."
Anyone wishing to donate to the Clark family burial fund can send contributions to the Betty Clark and Family Foundation, c/o Provident Bank of Maryland, 6400 Rossville Blvd., Baltimore 21237.