A sign held up by a Toronto Maple Leafs fan on Monday that mocked a slogan used in the wake of the Boston bombing has sparked anger on social media.

The fan’s blue-and-white sign read “Toronto Stronger” -- a play on the phrase “Boston Strong,” the popular slogan that was trending on social media in the wake of the deadly Boston Marathon bombings that killed three people on April 15.

The sign was spotted in Maple Leafs Square Monday night, where thousands of hockey fans gathered to watch Game 3 of the playoff series between the Leafs and the Boston Bruins.

The Bruins went on to beat the Leafs 5-2 that night, and now lead the series 2-1.

But photos of the sign quickly made the rounds on Twitter and Facebook, prompting outrage and scorn on both sides of the border.

Other Leafs fans also condemned the sign, but reminded people that it should not be equated with the city or all Leafs fans in general.

Some angry Boston fans used the sign to rally behind Boston and the Bruins as the series continues.

After practice Tuesday, Bruins coach Claude Julien dismissed the sign, saying it had nothing to do with the game.

“Last night’s sign, to me, had nothing to do with hockey,” he said. “Boston Strong is about something that struck our city, not our team. Maybe it's a little sensitive for the Boston people.”

He added that these incidents tend to happen during the playoffs, pointing to a Leafs fan who was reportedly assaulted after he left a game in Boston.

“Unfortunately the best and sometimes the worst comes out of the passion of our game,” he said.

With files from The Canadian Press