Montreal police are investigating a small bomb that exploded in front of the Ben Weider Jewish Community Centre on Tuesday night.

The late-night blast blackened the sidewalk in front of the Westbury St. Centre in Cote-des-Neiges, frightening several employees inside, police said. No one was injured.

Details are still sketchy but investigators said the the bomb was detonated around 11 p.m. ET. No one has claimed responsibility, and police have no suspects and have not received any notes or reports of threats.

Investigators are not calling the fire a hate crime, although they haven't yet dismissed the possibility, said Const. Marie-Claude Bérard.

But Jewish leaders suspect anti-Semitic sentiments may have motivated the attack.

"This is a Molotov cocktail that was not placed in a park: it was placed in a well-known public Jewish Institution [that is] visibly identified as such," said Steven Slimovitch, a Montreal lawyer with B'nai Brith.

The attack also coincides with Passover, a major holiday, Slimovitch said, adding the incident may prompt some to increase security measures at Jewish institutions.

"There is a specific security protocol with the Montreal police that is put into force during the High Holidays. I'm not aware of a synagogue in Montreal that you can get into without ID now," he said.

In 2004, a fire destroyed the library at the Talmud Torah Jewish School in St-Laurent, northwest of Montreal. Two people were arrested and charged after the incident.

With files from the Canadian Press