The social media app Yik Yak has been involved in another mishap at an Ottawa high school, just a few days after it was linked to fire alarms being pulled in pranks at four different schools.

Police say Hillcrest HS in the St. Laurent Blvd. and Smyth Rd. area  was put on lockdown for about 45 minutes Monday afternoon after a firearm on the property was mentioned in a conversation on the Yik Yak app.

Ottawa police were called the school around 12:30 p.m. They put the school on lockdown, and searched the property.

About 45 minutes later, they lifted the lockdown, satisfied the school was safe and that no gun was on the premises.

"Police responded immediately, assessed the situation and determined that the threat was false and that no danger was imminent," Barry Bickerton, the school's principal said in an email to parents Monday afternoon. "The incident was quickly and efficiently addressed in a safe manner," he added.

Last Thursday Yik Yak was linked to four successive false fire alarms at four schools in Orleans.

The app allows people to post and read messages anonymously within a set boundary and has been criticized for its use in cases of cyberbullying.