Paris (dpa) - In a bakery in the center of Paris there was an explosion on Saturday morning. Several people were injured, said a police spokeswoman for the German Press Agency, without giving details.

There was a fire, the explosion in the Rue de Trévise had been strong. The cause was still unclear, it said.

Originally, the fire department had been called to the bakery because of the escape of gas. The explosion occurred about a kilometer away from the Paris Opera. TV pictures showed massive firefighting, smoke came from the building. Several glass panes in the area were destroyed by the force of the explosion, media reported.

The authorities in Paris are on alert for announced demonstrations of the "yellow vests". Around 5,000 security forces are deployed in the capital to hedge the protests. During the demonstrations, there had been repeated violence and riots in recent weeks. Especially Paris was affected.