UPDATED:

A fatal shooting at the University of California, Los Angeles (UCLA) left two adult males dead at approximately 10:00 a.m. this morning.

Here are five things you need to know:

1. It was ruled a murder-suicide.

The Los Angeles Police Department, leading the investigation, ruled the shooting a “possible” murder-suicide. A source at Fox 11 reporting from the UCLA campus told The Daily Wire a murder-suicide has been confirmed and one of the victims was responsible for the shooting. A gun and a note were found on the shooter’s body. The deceased shooter’s motives are still being investigated.

2. The shooting took place near UCLA’s Engineering Building. Students were advised to remain on lockdown until further notice.

Mass alerts were sent periodically to the entire UCLA community:

9:54 AM

BruinAlert:

Shooting at Engineering 4. Go to secure location and deny entry (lockdown) now!

11:27 AM

BruinAlert:

Follow up: Shooting. Lock down continues for entire campus. Regardless of location on campus, go to secure location and deny entry (lockdown) now! More information once available.

Students were instructed by faculty to remain within their classrooms, lock their doors, and wait until further notice to leave.

Student Jason Schechter reported he and his colleagues had barricaded themselves in their computer lab on the 4th floor of the Engineering Building during lockdown. One of the students apparently urinated on the floor because he had no access to a restroom.

Schechter said he didn’t hear a gunshot but he heard a lot of police in the vicinity.

11:44 AM

BruinAlert:.

Lock down continues. Do not go outside unless instructed by UCPD! Do not come to campus. If outside go indoors and lock down.

3. Lockdown was lifted from the UCLA campus at approximately 12:00 p.m. but classes are canceled for the day as the shooting investigation continues.

LAPD announced the campus was safe, but that an investigation would continue. Classes and finals scheduled for June 1st are canceled for the day, and professors are allowing homework extensions as they recover from the incident.

12:18 PM

BruinAlert: All Clear.

Shooting event was an apparent murder/suicide. Lockdown is lifted at this time. Classes are cancelled for the remainder of the day and expected to resume tomorrow. Campus is open with exception for areas affected by the investigation. Check newsroom.ucla.edu for updates.

One photo indicated a professor was locked in his classroom but still attempted to get his students to complete their final scheduled for today:

4. The unarmed shooting victim was a biomechanics professor, William Klug.

Klug taught mechanical engineering at UCLA and was beloved by his students, some of whom are mourning his death by commemorating him online.

Kayla Boldt, a sophomore at Yeshiva University in New York City, told The Daily Wire she knew Klug and was supposed to meet with him in Los Angeles tomorrow to discuss interning for him at UCLA over the summer.

"I was suppose to meet with him tomorrow," Boldt, shocked by the incident, said. "Let me put it this way, I contacted about 40 professors to see if I could do research with them this summer. He was the only one who took me under his wing and offered me a position. He said he was a lot like me as a student, trying to grab hands on opportunities wherever he could."

Boldt added when she heard a shooting had occurred at UCLA this morning, she immediately emailed Klug to find out whether he was okay and still on for their meeting the next day.

"The not so funny thing is that when I heard about the shooting, before the authorities said that the two wounded were actually victims, I emailed him saying I hope everyone is safe and asking if it was still ok if I met with him tomorrow," she said.

5. Sources say the shooter was a student of Klug who was "despondent" about his grades.

KNX reporter Claudia Peschiutta tweeted that the shooter was a student who was upset with his grades and shot himself after shooting the professor. Peschiutta's tweet was not confirmed by officials, however.

UCLA's campus newspaper, the Daily Bruin, reports the law enforcement officials are refusing to identify the shooter and release details about his motives:

Officials said LAPD will continue to investigate the incident as a homicide. Beck said some officers reported evidence of a suicide note, but the note has not been confirmed.

The shooter, a male adult, was found dead with a gun. Officials said they could not release more information about the shooter’s identity.

Beck said only the Coroner’s Office is authorized to release identifying information about the victim.

Students are being instructed to avoid Westwood Plaza until further notice. Classes will resume tomorrow, Thursday, and scheduled finals next week will resume as planned. According to CNN, the Engineering senior class dinner is scheduled for Thursday night.

Boelter Hall, the Engineering building where the shooting reportedly took place, is where the internet was born when in 1969, the first transmission that would become the internet was sent.

UCLA, along with the other University of California campuses, remains a gun-free zone.

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