At least 13 people have died and six more suffered injuries in France in a fire at a bar in the country’s north.

The blaze erupted during a birthday party at a bar in the northern city of Rouen on Saturday.

“An inquiry is underway to establish the cause of the fire,” Interior Minister Bernard Cazeneuve said in a statement.

One source close to the investigation said that candles on a birthday cake may have sparked the blaze.

One of the injured was in a critical condition, according to the secretary general of the Seine-Maritime Prefecture, Yvan Cordier.