Three Comox Valley high schools were closed Thursday after a picture was posted to social media of two teenagers posing with what appeared to be guns.

The Comox Valley School District confirmed that high schools Mark R. Isfeld, G.P Vanier and Highland were shut down after police determined one of the three schools was not safe.

Some 3,000 staff and students were told to stay home out of precaution.

RCMP later confirmed two students were arrested for uttering threats and have since been released to the care of their parents.

"The information that we received was specific to one of the secondary schools," said SD71 spokeswoman Mary Lee.

Other schools in the district were briefly placed into hold and secure status, which was later lifted.

CTV News has obtained a picture posted to social media showing two youths posing with what appeared to be a rifle and revolver. The photo included text that said "shooter gang" and "don't come to school tomorrow."

An official, speaking on condition of anonymity, confirmed that the photo is the one that triggered the RCMP and school district's investigation.

"We have a system in place to deal with matters such as this. This incident was able to show that the system works," said Comox Valley RCMP spokesman Const. Rob Gardner. ”We must take all threats seriously and these investigations take time to ensure the safety of everyone involved.”

Investigators are also aware that the incident happened on the same day provincial exams were to be held in the district.

The district said schools will reopen as usual in the district Friday, and any exams scheduled for Thursday will be administered then.