The Boston Bruins and Toronto Raptors are among several teams across several professional sports leagues sending condolences to a junior hockey team after 15 of its players or coaches died in a bus crash late Friday.

The Humboldt Broncos, who play in the Saskatchewan Junior Hockey League (SJHL), were traveling to the town of Nipawin for a playoff game at the start of the weekend when a transport truck collided with the team bus. Canadian police have confirmed that 15 of the bus' 28 passengers have died, while the other 13 have been transported to the hospital with injuries -- three of them critical.

Saturday morning, the Bruins tweeted that "our hearts are heavy this morning" and assured the Humboldt community that "the hockey world is with you at this time."

The NBA's Raptors did the same, echoing comments from Canadian prime minister Justin Trudeau, USA Hockey and various NHL players.