Carlsbad High School has canceled classes for Tuesday following a reported Instagram threat to "shoot up" the school put the campus on lockdown on Monday.
School officials haven't been able to rule out that a threat won't happen, said Carlsbad Unified School District Assistant Superintendent Rick Grove.
Carlsbad Village Academy also has canceled classes for Tuesday, as it is housed on the same campus.
Students were sent home early Monday after the reported Instagram threat.
The students were released at 11:15 a.m., though the school said teachers would be at school up until the last student went home, according to a post on their website.
Grove said the threat was reported by a parent Monday morning. The school is waiting for police to finish their investigation.
Everyone is safe, according to a tweet sent out by the superintendent of Carlsbad Unified School District during the lockdown. School is expected to resume tomorrow.
The police department was on scene.
Check back for more on this developing story.