Paris, France (BBN) – An explosion and subsequent fire ravaged a bar in northern France early Saturday, leaving 13 people dead and several others wounded, authorities said.

Initial reports indicate the explosion in Rouen, Normandy, was accidental, according to the Rouen Police Department, reports CNN.

Local media reported the bar was hosting a birthday party at the time, and the victims were between ages 18 and 25.

Following the incident, a major street was blocked and a security perimeter set up around Le Cuba Libre Bar, a witness said. Firetrucks and several police vehicles swarmed around the bar on Avenue Jacques Cartier.

France has been on high alert following a spate of fatal terror attacks. About two weeks ago, two jihadist attackers killed a priest in Rouen.

During Bastille Day celebrations on July 14, a man who pledged allegiance to ISIS plowed through crowds gathered to watch fireworks in Nice, killing at least 85.