A lockdown at three Meridian schools is over.
The schools went into lockdown for about 45 minutes late Thursday morning.
Meridian school district spokesman Eric Exline said Centennial High School's resource officer had noticed a student by himself in the gym during a time when no one should have been in there. The student fled the building as the officer approached. The school went into lockdown while officials searched the gym for any signs of anything suspicious and tried to locate the student, whose identity is known.
As an extra precaution, officials also locked down nearby Joplin Elementary School and Lowell Scott Middle School.
Exline said everyone at all three schools is safe and no one was injured.
Meridian has been on heightened awareness this week and school district officials and police are planning to take extra precautions on Friday in response to possible threats.
Two Meridian high schools have cancelled assemblies planned for Friday and police will have an increased presence in at least one high school following a threat that something bad would happen at a Meridian high school on Friday.
Exline said rumors started circulating among students on Monday that something was going to happen during an assembly at Centennial on Friday, but it wasnt clear what was going to happen.
Since then, the communications have increased and the threat has evolved to include references to a gunman and additional schools Rocky Mountain, Mountain View, Meridian and Eagle high schools.
The majority of the threat-related communication has taken place through text messages and social network sites. Somebody got a text message from somebody saying they heard something bad was going to happen, Exline said.
Officials have been trying to trace the messages to find the original source, but have not yet found it.
Exline said school officials and police decided to take extra precautions, including canceling Friday's assemblies at Centennial and Mountain View.
On Friday, Boise police will be on site at Centennial, which is a Meridian school but located in Boise.
For the other high schools on Friday, each schools assigned resource officer will be more visible and Meridian police, which had already increased patrols around schools following last weeks mass shooting at an elementary school in Newtown, Conn., may add even more patrols.
Boise school district does not have school on Friday.