Four people have been arrested during a Gatineau Police operation in the Aylmer sector.
A perimeter was set up on rue Thomas as police responded to reports of a firearm at a home on the street.
The incident began around 1:30 p.m. Thursday.
Some students at the nearby school, École internationale du Village, reportedly spotted the firearm on Tuesday, but police were only informed of this Thursday afternoon.
Thursday's investigation confirmed a firearm is present in a home at 17 rue Thomas.
Police say the students at the school were not at risk. They were kept at the far side of the building when the operation began, and were evacuated safely at the end of the school day.
Police have not said why the four individuals have been arrested and have given no word on any charges they might be facing.
The investigation is ongoing.
With files from CTV Ottawa's Eric Longley.