A lockdown at SickKids hospital has ended after police received a call about a “threat to public safety” on Sunday night.

Police were called to the hospital at Gerrard Street West and University Avenue around 10:15 p.m. on Sunday. Officers carrying rifles scoured the area and gates at the hospital’s emergency room entrance were brought down.

Around the same time, the Alberta Children’s hospital in Calgary and a children’s hospital in Edmonton also went into lockdown.

Police tactical units searched the Calgary hospital but found nothing.

All three areas have since been cleared by police.

Toronto police say they have been in contact with officers in Calgary and Edmonton over the similar calls.

Police in Calgary confirmed that the incident there was one of swatting.

There has been no word if the three incidents are connected.