(CNN) An armed man carrying a gas canister attempted to barge into a Moscow synagogue Saturday and wounded a security guard who tried to impede him from entering the building, police told CNN.
The man has been detained, and the security guard has been hospitalized, police said.
According to a security source, cited by state media, the man threatened to torch the Moscow Choral Synagogue.
A motive is not yet known, and authorities haven't said whether the suspect is connected to a group.
The attack took place on the Jewish Sabbath, which falls on Saturday, and occurred a day before Rosh Hashana, the Jewish New Year, which starts Sunday evening.
The synagogue is one of the country's oldest, according to its website.
"Since the day of the grand opening on June 1, 1906, the synagogue has been active without interruption, and has remained the center of the religious and social life of the Jewish people in Russia," the website says.