BAKERSFIELD, Calif. (KGET/KRON) -- A Livermore man who was convicted of a 2012 murder died in prison Thursday after an apparent attack with an inmate-manufactured weapon, prison officials said. Jacob Kober, 35, was an inmate at Kern Valley State Prison. His cellmate also suffered injuries in the attack. Kober was pronounced dead at 7:52 p.m., about 30 minutes after prison staff found him wounded and unresponsive in his cell, according to a release from the California Department of Corrections and Rehabilitation. Man arrested for 1987 San Jose strangulation homicide His cellmate, Matthew Perez, 39, also had injuries and was taken to an outside medical facility, the press release says. An inmate-manufactured weapon was found in the cell, according to CDCR. Both men's wounds appeared to have come from it. An investigation is ongoing. Kober was serving a life term after being convicted of first-degree murder for a fatal shooting in December 2012. The victim, Kenneth Robert Ogden, was found in the grass alongside the Springtown Golf Course fairway. The Alameda County District Attorney's Office said Kober and Ogden were longtime friends until they had a falling out. The argument was over Ogden owing Kober money and allegedly trying to kiss his girlfriend. Kober was arrested in Oregon in January 2013. Perez is serving 18 years for a 2012 conviction of assault with a gun in Monterey County, eight years for a 2014 prison assault and two years for a 2016 conviction for having drugs in prison.