SAN FRANCISCO (CBS SF) — Friends and investigators were at a loss Thursday to explain what drove a San Francisco UPS driver to pull out a gun at a work meeting and kill three colleagues who police suspect were targeted.
Jimmy Lam, an 18-year veteran of UPS, appeared to single out the three slain drivers, but investigators have yet to determine what set him off on Wednesday, an official in the San Francisco Police Department said.
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The person was not authorized to discuss the case publicly and spoke on the condition of anonymity.
The victims in the shooting have been identified as Wayne Chen, Mike Lefiti and Benson Louie.
Lefiti, 46, and Louie, 50, had each worked for UPS for 17 years, according to the company. Chan, 56, had 28 years of service.
Joe Cilia of the Teamsters Union said Lam started working for UPS in 1999. He has only filed one grievance at the job, one submitted earlier this year because he had been assigned extra overtime for more than 3 days in a row.
But no one who works at UPS believes that's what set Jimmy off and led him to march into the morning meeting armed, and opening fire on his three fellow drivers.
Cilia said Lam first shot Benson and Wayne inside the meeting room before chasing Lefiti outside and shooting him as well.
When police arrived, Lam turned the gun on himself.
Cilia believes the two people who were wounded were unintended victims in the crossfire.
None of the men who were shot were managers, Cilia noted, adding that he knew of no disputes between Lam and the victims.
Lam, 38 years old, lived in the Sunset District.
Cillia said he did know that Lam was stressed out -- because he put it in writing.
He noted that excessive overtime is standard at the San Bruno Avenue facility. The union has seen a spike in grievances this year.
"Most drivers don't mind the 9.5 10 hours," explained Cillia. "It's the 11, 12, and 13 [hour days] that interfere with their life."
KPIX 5 also learned Lam had a criminal history. All of the charges stem from issues behind the wheel.
Court records show Lam had been charged with two DUIs, while driving his personal car.
The first one in 2010 included hit-and-run charges. The second DUI was three years later, while charges were dropped, lam's license was suspended and his probation extended.
"Once a driver has a DUI, they have to report it to management so they are aware," said Cillia.
Cilia said UPS has a program to take drivers off the road to help them rehabilitate before letting them back behind the wheel.
He believes the rehabilitation process is thorough and fair, but the overtime isn't.
"When I started in 87 overtime was mostly October, November, December. Christmas, said Cillia. Now with everyone shopping online all the time its really changed this business"
Friends and colleagues recounted several personal and professional troubles that Lam had been experiencing.
Shaun Vu, a senior UPS driver, said Lam had personal troubles a few years ago that involved a dispute with a girlfriend over visitation rights for their young child. Vu said he encouraged Lam to seek professional help and that Lam took off work for several months.
Lam seemed fine when he returned to work but Vu noticed a few weeks ago that he looked troubled.
"I just saw him passing by and asked how he was doing," Vu said. "He said something like, 'I'm hanging in there.'
"I don't think he had anybody he could talk to and it got worse and worse," Vu said.
On Thursday, friends and family continued to mourn the loss of the three men who were killed.
"I've been crying for the last day," said Frieda Neiman of San Francisco. "This is just... such a tragedy."
Besides their jobs as UPS drivers, the three men were also beloved members of their families and their communities. Benson Louie was a volleyball coach.
"To us on the team, he was like a second father," said Joe Schow, a friend and volleyball teammate to Louie.
People in the Sunset were also remembering their lost friends.
"I've known Benson since middle school," said Donna Wong-Kyono. "The world lost another great person."
"I've been at this store almost 40 years and he's been the guy," said Margaret Lee of Harvest Christian Bookstore. "He was more than a UPS driver. He was my friend."
Isaiah Miggins, a UPS loader on the overnight shift, said it was hard to finish his shift.
"Everybody was down," Miggins said, adding that UPS is like the U.S. Post Office: "We gotta get those packages out."
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