UPDATE: 4:11 p.m.: Livermore Police confirmed Friday afternoon that Livermore High School was locked down as a precaution around 3 p.m.
As of 4 p.m., students had been released and one police car was still at the school.
No further details were available, but there were reports of a possible robbery at a Bank of America in downtown Livermore about 40 minutes before the lock down.
According to a Patch reader Siobhan Tyler from Facebook, parents recieved an automated phone call from the school district about the incident.
"Just received an automated message from the school district. There was a suspect that fled in the general direction of Livermore High. They put Livemore High, Junction, East Ave and St. Michaels on lock down at 2:45. They apprehended the suspect and lifted the lockdown at 3:10."
Tensions were already high in the school community about safety, as earlier today the public was concerned about someone who reportedly claimed they were going to bring a gun to a Livermore high school campus today. Posts on Twitter Thursday mentioned that someone had threatened to do this.
Tensions are high at many Bay Area schools following last week's massacre at Sandy Hook Elementary School in Connecticut.
On Thursday a parent of a Dublin High student contacted Patch saying they had heard of a bomb threat, but Dublin Police said it was just a rumor. Threats were also made to a school in Pleasant Hill on Monday.
Dublin Unified Superintendent Dr. Steven Hanke said Friday there was not a bomb threat and that school officials have been keeping a close eye on things on campus.
"We have been very vigilant on campus," said Hanke. "We are making sure there is an ongoing sense of calm to help keep the focus on learning."
In Oakland Friday morning, a series of phone calls to the school threatened students, a school district spokesman said. Hoover Elementary School went on lockdown around 9 a.m. after the school received multiple calls from someone threatening to harm students, Oakland Unified School District spokesman Troy Flint said.
School district and city police responded to the school and have formed a perimeter, Flint said.
Bay City News Service contributed to this report.