The victims in today's shooting at UCLA have been identified as a professor and a student.

Sources tell CBS News that the professor was William Klug of the university's Department of Mechanical and Aerospace Engineering. The student, who is believed to be the shooter, has not been identified.

Update 6/2: The shooter has been ID'd as Mainak Sarkar, a former doctoral student who accused Klug of stealing his computer code.

BREAKING. Sources tell @CBSNews the 2 people shot in the UCLA murder-suicide were a student and a professor, William Scott Klug. (1/2) — Charlie Kaye (@CharlieKayeCBS) June 1, 2016

More UCLA (2/2) The name of the student, who sources say was the shooter, is not known. — Charlie Kaye (@CharlieKayeCBS) June 1, 2016

Victim in UCLA murder-suicide ID'd as Professor William Klug, Eyewitness News has learned https://t.co/26jirqz3Zz pic.twitter.com/hYtoX2peUd — ABC7 Eyewitness News (@ABC7) June 1, 2016

According to Klug's personal research group's website, his area of study was focused on biomechanics. Klug's staff bio on the engineering department's website says he earned his PhD from Caltech in 2003.

A law enforcement source told KNX's Claudia Peschiutta that the shooter was upset about his grades:

#UCLAshooting: Student apparently despondent about his grades shot professor & then killed himself, according to law enf source. @KNX1070 — Claudia Peschiutta (@ReporterClaudia) June 1, 2016

Classes wrap up for the spring quarter at the end of this week, and some students were already taking their finals when the shooting took place on Wednesday morning.

While the entire campus was on lockdown and classes were canceled for the day, UCLA Executive Vice Chancellor and Provost Scott Waugh said normal operations would resume on Thursday. "We want to resume normal operations as quickly as possible, so we will resume scheduled classes tomorrow morning," he said in a release.