(LOS ANGELES) -- The shooter who allegedly killed a UCLA professor and then himself on campus Wednesday has been identified as Mainak Sarkar, ABC News has learned.
Investigators are focusing on his grades and what’s being described as a "longer-standing" poor relationship between the two men.
The professor has been identified as William Klug, according to two law enforcement sources.
The Los Angeles Police Department said it believes Klug was the shooter's teacher.
Investigators worked through the night to understand what happened and why. Officials are planning to release more details on the deadly incident Thursday morning.
The shooting occurred Wednesday morning in one of the engineering buildings on the Los Angeles campus. The school was put on lockdown.
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