A threat of violence against Jordan High School started circulating on Instagram Sunday night, prompting Long Beach police to take three 15-year-olds to juvenile hall.

Authorities said they don’t think the threat was credible. Police searched the home of at least one of the teenagers who made the threat and found no weapons, according to Long Beach police spokeswoman Arantxa Chavarria.

Students noticed the threatening post against Jordan on Sunday night and immediately reported it, Long Beach Unified School District spokesman Chris Eftychiou said.

Police said they were first called about it at 9:30 p.m. Sunday when a boy reported he’d seen the threat on social media.

About two hours later, a teenager called police dispatch and told them he was the one who posted the threat, according to police.

“He was taking ownership of the post,” Chavarria said.

Detectives eventually were able to connect two more 15-year-olds with the threat, although Chavarria couldn’t immediately explain exactly how they were involved.

All three teenagers were held on suspicion of making terrorist threats and booked into Los Padrinos Juvenile Hall, according to police. Detectives will present prosecutors with a case against them in the near future, Chavarria said.

“The Long Beach Police Department takes all threats of violence seriously and fully investigates each incident,” Chavarria said. “We worked with the Board of Education to ensure the students, parents, and staff were safe. Detectives do not believe the security of students was compromised at any point during their investigation.”

All three teenagers are from Long Beach, Chavarria said. Authorities declined to say where they attended school.

Editor’s note: This story was updated Tuesday morning with more information from police. An earlier version of this posted Monday said the suspects taken into custody were students. Authorities have not answered questions about whether the suspects were students.