A Palestinian woman who set off a bomb in downtown Jerusalem, killing an elderly Israeli man, injuring dozens and causing widespread damage, was a paramedic who was profoundly affected by the wounded Palestinians she treated, relatives said yesterday.

The Al Aqsa Martyrs Brigade, affiliated with Palestinian leader Yasser Arafat's Fatah movement, claimed responsibility for the Sunday bombing, calling it a "martyr operation" in a statement yesterday, usually code for a suicide bomb attack. That would make Wafa Idris, 27, the first woman to turn herself into a human bomb during more than 16 months of Palestinian-Israeli violence.

Idris, from the Amari refugee camp next to the West Bank town of Ramallah, was a Red Crescent paramedic who was often called to the scene of clashes to treat Palestinians wounded by Israeli gunfire. She herself was hit three times by Israeli rubber-coated bullets, relatives said.

At the camp yesterday, relatives said they were surprised to hear she had become a suicide attacker, but a sister recalled her saying once that she wanted to die "a martyr," the term Palestinians use for people killed fighting Israel.

They said they did not know of her affiliation with the Al Aqsa group, though three of her brothers are Fatah activists.

Her attack came just a day after Arafat, confined by Israeli tanks to his Ramallah compound, said in a speech: "Please, God, give me the honor of being one of the holy Jerusalem martyrs."

Israel blamed Arafat for the bombing, charging that he was encouraging Palestinians to attack Israel.

Known as cheerful but sometimes hot-tempered, Idris would come home from the clashes in an altered state, relatives said.

"Usually when she came back from work, she would tell us stories about the injured people she had treated and she looked affected," said a sister, Wisam Idris. "She used to say, 'If I die, I want to die as a martyr.'"

When Idris did not return from work Sunday afternoon, the family called her cellular phone - but got no answer. They said they had no idea that she was headed to Jerusalem with a bomb.

A maintenance worker shot a female school bus driver yesterday as she was preparing to start her route, then fatally shot himself, the Muskingum County coroner said. No students were in the area at the time.

Deborah Law, 41, of Zanesville, was shot three times and was hospitalized in critical condition, the county sheriff's office said.

The shooting happened about 6:20 a.m. at the Zanesville public school district's bus garage about 55 miles east of Columbus.

The shooter walked onto the bus, shot the driver and then shot himself with a semiautomatic handgun, said Sgt. Dan Marks, spokesman for the sheriff's office. Coroner Howard Marsh identified the man who died as 59-year-old Ron Melvin Sr.

The school district, which has about 4,600 students, canceled classes after the shooting.

U.S. Customs Service inspectors along the Arizona-Mexico border said yesterday that a 1,700-pound marijuana load has been seized from a travel trailer driven by a South Dakota man.

Inspectors said a pickup truck towing a trailer from Mexico was stopped Tuesday at the Mariposa port of entry.

A customs drug-sniffing dog searched the trailer and alerted inspectors to its mirrored rear wall.

When the mirror was removed, inspectors said they found a hidden compartment with 1,370 marijuana-filled tin cans.

The driver of the trailer, Ruben Deleon Balderas, 52, of Eagle Butte, S.D. was arrested by customs agents.

Inspectors said there were four other drug seizures at the Nogales port Tuesday that netted 54 pounds of marijuana and 12 pounds of cocaine