A man has been detained after police received a call that someone had made an unspecific threat against Helix Charter High School, police said.
Just before 9:00 a.m. on Friday morning, El Cajon police received a suspicious phone call. The information was given to the La Mesa Police Department, who relayed the information to school officials.
A message posted on the school's website said the school went to a secure campus.
"Due to criminal activity in the area, Helix Charter High School has gone to a secure campus and is working with the La Mesa Police Department to resolve the issue. Please do not come on campus until we have clearance," the school website reported Friday morning.
"It wasn't a specific threat, but it raised some concerns," said La Mesa police Lt. Dan Willis.
Using the information from police the school's executive director, Rani Goyal said she decided to go to a secure campus.
Officers were seen searching the campus, while students were kept inside. Helix teachers were instructed to lock their doors and continue teaching their class.
One student said her teacher took extra precautions by making them sit on the floor with their backs along the wall.
"It was really scary," said Shanel, a student at Helix.
Shanel text messaged her mother who showed up at the school to see what was going on, as did several other parents who received word from their kids.
Curtis Swafford, whose son attends Helix, showed up at the school after receiving a phone call.
"Someone called me on my cell phone and said there is a bomb threat at your son's school," Swafford said.
In case of emergencies, Helix officials can choose to go to a secure campus or a total lockdown.
A secure campus means that students are locked inside their classroom, but instruction continues, Goyal said. A school-wide lockdown means that the lights are turned off in the classroom and students sit under their desks, Goyal added.
El Cajon Police were able to trace the phone call. Officers detained a man in his 40's at an El Cajon home. They said they will conduct a mental evaluation on the man.