Updated

SAN JOSE, Calif. -- The husband of a graduating business student at a Northern California university shot and killed her and a male classmate in a car in a campus parking garage then turned the gun on himself, officials said Thursday.

Victims Marcory Caliguiran, 25, and Thomas Kyle Williams, 26, were honor students who were about to graduate with accounting degrees from San Jose State University, school spokeswoman Pat Lopes Harris said.

Police said they were sitting inside the car Tuesday night when Napoleon Caliguiran, 54, fired multiple shots from outside the vehicle owned by the married couple.

The gunman then shot himself, police said.

Police have yet to determine a motive for the attack, but campus police chief Peter Decena said it was being investigated as a domestic violence incident. Napoleon Caliguiran had no known criminal record, Decena said.

"We don't know a lot, and we may never know a lot about the series of events that led up to what happened in our parking garage," Harris said.

Williams, known to his friends as "Kyle," was recently recognized during an on-campus ceremony for making the President's List with a 4.0 average, said his father, Thomas Williams.

The elder Williams said his son had been married for three years and was scheduled to start a job with PricewaterhouseCoopers in San Jose in the fall.

"He was a terrific son with a lot of drive, smarts and ambition," Williams said. "He was at the top of his class with a bright future ahead of him. This is a big blow to our entire family."

Marcory Caliguiran, known as "Cindy," may have been giving Williams a ride home, said Howard Turetsky, an accounting professor and faculty adviser of Beta Alpha Psi, an honors organization that included Marcory Caliguiran and Williams as members.

"They were both phenomenal students," Turetsky said. "What a horrific tragedy."

Turetsky said the students worked on projects together and were not involved in a romantic relationship. Williams was devoted to his wife, Katie, the professor said, as he read a posting she put on Williams' Facebook page.

"I will love you forever my boo bears, there will never be a goodbye because you will always be with me!" Katie Williams wrote. "You made me a very happy woman and for that I will always be grateful ... Look how many people love you, baby.

"I will be fine, I hear your voice and I'm doing what you're telling me."

Careerwise, Caliguiran had several job prospects, Turetsky said, adding a recruiter from PricewaterhouseCoopers was devastated over the death of Williams.

Thursday's announcement also hit student body president Tomaz Kolodziejak especially hard. He knew Williams and took classes with Marcory Caliguiran, whom he knew as "Cindy" and recently worked with on a 40-page senior project.

Kolodziejak said he spoke with the honors student frequently and thought something was wrong when the usually reliable Caliguiran didn't show up for class Wednesday.

"We started calling, texting, emailing her," he said. "She didn't respond. So the whole day was sort of terrifying. We thought it could be her, but nobody wanted to believe that. We thought maybe she was sick."

Despite their frequent contact, Kolodziejak didn't know that Caliguiran was married. He said classmates often walked her to her car to ensure her safety, and he believes that's what Williams was doing when they were killed.

"It's just so hard to believe," Kolodziejak said, fighting back tears. "She was a really passionate, hard-working person. Just the sweetest."

The slayings are believed to be the first shooting deaths in the 150-year history of the nearly 30,000-student commuter campus in the San Francisco Bay area.

Students had waited anxiously for more than a day to learn the names of the victims and whether they were campus students. A collective gasp could be heard when Harris released the information at a news conference.

"There is a great feeling of sadness," Harris said.

Harris said school officials were working closely with family members, including those of Marcory Caliguiran in the Philippines.

Students preparing for final exams next week will be offered counseling to cope with the tragedy.

The victims will likely receive posthumous diplomas and be honored during an on-campus memorial.