The emergency room at the Hospital for Sick Children in Toronto was on lockdown for several hours overnight.
Hospital officials said a “low risk” situation prompted the lockdown of the ER Sunday night.
Officers surrounded the building for hours but the lockdown order was lifted just before 6 a.m. on Monday.
Police would not comment on the specifics of the incident.
READ MORE: Alberta Children’s Hospital put on lockdown Sunday
A similar situation forced a lockdown at Alberta Children’s Hospital in Calgary on Sunday night.
Police responded after someone reported an incident involving a firearm around 8:15 p.m.
Several units were put on lockdown but officers and hospital security staff conducted a sweep of the building and found nothing. The lockdown was lifted at 9:40 p.m.
READ MORE: Threat to Stollery Children’s Hospital in Edmonton
Meanwhile, an unspecified threat was also made to Stollery Children’s Hospital in Edmonton on Sunday. Officers attended the scene but nothing was found.
Police did not reveal the source of the threat.
VIDEO: Alberta Children’s Hospital put on lockdown
—With a file from Lisa MacGregor