LONG BEACH (CBSLA) — California State University Long Beach police have arrested a male student in connection with a threat made against the campus Monday afternoon after they said he gained access to a female student’s email account to send the threat.

CSULB police said they were forwarded an email with what they deemed a “credible threat” and sent out an alert to students to shelter in place or to stay away if they were not yet on campus.

READ MORE: CHP Motorcycle Officer Involved In Traffic Collision On Eastbound 105 Freeway At Bellflower Boulevard

“It was a threat to shoot up the campus,” CSULB police Capt. John Brockie said. “It was a threat of violence.”

Videos and photos posted to social media showed how students responded to the temporary lockdown.

“That was in fact, my sister,” Zachary DeVore, a student, said. “They went into full lockdown, table against the door, as many heavy objects against it as they could get and then hiding in a corner out of sight.”

RELATED: CSULB Students Concerned About Safety Following Monday Afternoon Lockdown

READ MORE: First Weekend Eligible Adults Can Receive Pfizer's COVID-19 Booster Shot In Los Angeles County

While students, faculty and staff sheltered in place, police said they tracked down the female student who owned the email address that sent the threat, but investigators determined that she was not the one who sent the threat.

After she was released, investigators questioned a male student, identified as 18-year-old Prateek Devulpally, who was later arrested.

“During the interview, [he] confessed to using the female’s email address to send the threatening email to the university,” Brockie said.

Police said they were still trying to determine a motive.

“I don’t know if he knew her or he had something against her, his intentions were bad toward her or if she was just somebody he just picked up at random,” Evelyn Mercado, a student, said.

MORE NEWS: Man Shot And Killed By Huntington Police Saturday As Nearby Crowds Watched U.S. Open Of Surfing

Devulpally is being held on $50,000 bail and investigators said they plan to ask the district attorney’s office for two felony charges.