Authorities on Wednesday charged five former members of a 1970s radical group in a 26-year-old murder case, finally responding to a Riverside man's quest to solve his mother's murder.

Dr. Jon Opsahl spent the past 18 months urging Sacramento prosecutors to take another look into his mother's slaying at a bank outside Sacramento in 1975. Some people praised his quest; others ridiculed him for not letting go.

Opsahl then received a phone call Tuesday. Prepare to travel to Sacramento for a press conference the next day, a detective said. A second call came at 8 a.m. Wednesday. Arrest warrants had been issued for five people, including former fugitive Sara Jane Olson. All belonged to the radical Symbionese Liberation Army, just as Opsahl had long suspected.

Following the first conversation, Opsahl hung up the phone and cried tears of joy, said his wife, Theresa. Finally, someone could stand trial for firing a shotgun blast into Myrna Opsahl's stomach while she deposited church collection-plate money at a bank in Carmichael.

"All I ever wanted was for the Sacramento district attorney to investigate the evidence and hold the killers accountable," said Opsahl, whose 42-year-old mother was raising four children with her husband when she died. "There is definitely a feeling of satisfaction."

Authorities say Emily Harris was arrested at her home in Los Angeles. Police picked up her ex-husband, Bill Harris, in Oakland, while Mike Bortin was arrested in a suburban area outside Portland, Ore.

Arrest warrants were issued later for James Kilgore, who has disappeared, and Olson, who was expected to turn herself into Los Angeles authorities late Wednesday. All face first-degree murder charges.

"Now is the time to seek justice for Myrna Opsahl," said Sacramento District Attorney Jan Scully said.

She said "old and new materials" provided enough direct and circumstantial evidence to file charges. The FBI crime laboratory was able to link shotgun pellets that killed Opsahl to shells found in an SLA hideout in San Francisco, she said.

The arrests came with Olson, a former SLA fugitive, facing sentencing Friday in Los Angeles Superior Court. Olson pleaded guilty to her role in a failed attempt to blow up police cruisers with pipe bombs in 1975 to avenge the deaths of six SLA members in a shootout with officers a year earlier.

Bortin is married to one of Olson's sisters and attended some of her Los Angeles court hearings. Shawn Snider Chapman, one of Olson's defense attorneys, said the arrests surprised her.

"I question the timing of this," Chapman said. "It's my understanding that Bill was arrested in front of his children."

During the two years she has investigated the Olson case, Chapman said, "all I've learned and all I've read is that they consider this to be an unprosecutable case. All these people have been snatched from their homes for nothing."

The Harrises have already spent eight years in prison for kidnapping newspaper heiress Patricia Hearst. Emily Harris has been living in Southern California under an assumed name and works as a computer consultant.

Bill Harris is remarried, the father of two, and working as a private investigator. Bortin, who spent 18 months in prison for possession of explosives, is married and has a flooring business.

For more than two decades, Sacramento authorities said they didn't have enough information to make an arrest. The claims infuriated Opsahl because Hearst wrote a book asserting that she was in the getaway car during the robbery of Crocker National Bank in Carmichael. Hearst, who was kidnapped by the SLA, claimed that Emily Harris told her she shot Myrna Opsahl.

Hearst also wrote that Bortin and the Harris couple were joined by Kilgore and Olson.

Olson, who at the time of the pipe-bomb crime was known as Kathleen Soliah, later lived in hiding under an assumed name in Minnesota.

Many have praised Opsahl for lobbying Sacramento authorities to take another look at evidence that was only getting older, and colder, by the day. The Loma Linda University Medical Center preventive medicine specialist was consumed by their inaction, spending endless hours of free time investigating and making calls from his physician's office in Colton.

Opsahl created a Web site filled with evidence to show the case could be prosecuted, taking calls from reporters around the country.

His detractors said he should release his anger and stop bothering authorities. Notes posted on his Web site's message board labeled him part of the problem, not the solution. His wife found such claims upsetting.

"It has been very, very consuming, and rightly so," Theresa Opsahl said before becoming overcome with emotion and sobbing on the telephone. "I am grateful for his work, as his family is. It shows he wasn't just pointing fingers."

Opsahl said he will happily retreat into the background and let justice be served. His only plan now is to repair his mother's grave site. Soon after she was buried, someone vandalized a granite portrait of her face.

"It's actually appropriate in a way because she's kind of been a faceless victim for 26 years," he said. "Now we can change that."

Reach George Watson at (909) 782-7548 or gwatson@pe.com

The Associated Press contributed to this report.