At least seven people, including two children, have been killed in an explosion and subsequent fire that occurred in apartment buildings in southern France.

Officials said a search is ongoing for at least two people who are missing.

French interior minister Gerald Darmanin went to the site in the town of Saint-Laurent-de-la-Salanque and said about 30 people were wounded or suffered psychological trauma in the incident that occurred around 2am.

(SDIS66/AP)

Mr Darmanin tweeted his “full support” for emergency services and said his thoughts were with the victims and their loved ones.

Local radio France Bleu Roussillon reported that the explosion occurred on the ground floor of a two-storey building, which was a grocery-sandwich bar.

The fire then spread to neighbouring buildings.

Perpignan prosecutor Jean-David Cavaille said it was too early to know what caused the explosion but he mentioned the possibility that gas cylinders may have been present in the shop.

An investigation is already underway.