The Kristen Modafferi Mystery: Persons of interest in 20-year-old case speak out

SAN FRANCISCO (KGO) -- Friday marks exactly 20 years since Kristen Modafferi, a North Carolina college student living in Oakland, disappeared after leaving her job in San Francisco.

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The unsolved case dominated much of now-retired Oakland police officer Pat Mahanay's career.

"There must have been some stones unturned otherwise ... we'd have it solved by now," he said, thinking back on the mysterious case.

The unsolved case dominated much of now-retired Oakland police officer Pat Mahanay's career.

"There must have been some stones unturned otherwise ... we'd have it solved by now," he said, thinking back on the mysterious case.

The 18-year-old from Charlotte had moved to the Bay Area for the summer to take classes at UC Berkeley. She found a room online and rented the space on Oakland's Jayne Avenue. It was June 23, 1997, when Modafferi left work at a coffee shop in San Francisco and vanished.

Her family can't fathom why she didn't come home.

"If she hasn't passed on, then our imagination of what could be happening to her is horrific," said Allison Modafferi, Kristen's elder sister. "We know, without a doubt, that if she was able to reach us, she would reach us."

For three weeks after Kristen went missing, the Modafferis covered the Bay Area with her picture. Then finally, they got a tip, Mahanay said.

"This one was strange in that ... it was called to a local news station," he said.

Former ABC7 News Assignment Manager Bill McGee took that call.

"His story was that two women killed -Kristen- in a lesbian love triangle," McGee recalled. "He went into a lot of detail about who they were, names, places."

Police determined Jon Onuma, a man who lived about a mile from Kristen's work, made the call. He was trying to pin Kristen's case on two women who worked with his then-girlfriend Jill Lampo.

Police cleared Lampo's coworkers after questioning them.

Lampo agreed to an on-camera interview, if her face wasn't shown. She said she was at the library on June 23 and repeatedly showed us a library card.

We asked her about Onuma's call to the newsroom.

"To me, that would imply guilt," she said. "If you're going to call and draw attention to yourself, that implies -you- want attention for some reason."

Onuma was squarely in the sights of investigators and also got attention in an "America's Most Wanted" episode. On the show, women accused Onuma of attacking them. He's never been charged.

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"He hit me over the head ... and said 'you know I'm going to have to kill you. I can't let you go,'" one accuser, in silhouette, said. "Then he turned around and said, 'now you know what happened to Kristen Modafferi.'"

ABC7 News reached Onuma on the phone. He no longer lives in California and did not want the conversation recorded. He admitted to calling the newsroom and said he's remorseful about it.

"I put the attention on me when I shouldn't have, and I screwed up," he said. "I took the focus off the investigation."

Onuma said he never met Kristen. Lampo said she hadn't met her either and couldn't prove whether Onuma had ever encountered the teen.

The FBI still has Kristen's picture, as a missing person, on its website. An FBI spokesperson said they cleared Onuma and Lampo as a persons of interest and closed the bureau's case.

Oakland police's file on the case, however, remains open - and they consider Onuma and Lampo persons of interest.

The unsolved case is still very present on Mahanay's mind. "At times, it keeps me up at night," he said.

And for Kristen's family, there has been no closure.

"There really isn't a day when we're not thinking about Kristen," said her father, Bob Modafferi.

The Modafferis hope someone else is also thinking of Kristen and calls in a tip.

Tips can be made to the Oakland Police Department's Missing Persons Unit at (510) 238-3352 or (510) 238-3370.

A Modafferi family friend also runs a website the where anonymous tips can be sent.