Four people, including two firefighters, have been killed after an explosion caused a huge fire at a bakery in the French capital, Paris, officials say.

Cars were wrecked and other buildings were damaged by the blast on Rue de Trévise in the 9th Arrondissement.

A gas leak is said to have caused the explosion around 09:00 (08:00 GMT).

Paris and other cities have been bracing themselves for new anti-government protests.

Helicopters landed on the nearby Place de l'Opéra to evacuate the injured, Reuters news agency reports.