Police in France have arrested a man suspected of planning attacks on churches, according to the country's interior minister.

Bernard Cazeneuve said that the 24-year-old man, an Algerian, was planning to attack "one or two churches".

He was known to security services and had expressed a wish to travel to Syria.

The man was detained on Sunday after he called for an ambulance, having apparently shot himself by accident. A car was seized along with handguns, other weapons and bulletproof vests. Notes "unambiguously demonstrating" he planned an imminent attack were found, said Cazeneuve.

The man is also suspected of involvement in the death of a 32-year-old woman, Aurelie Chatelain, who was found dead in her car on Sunday. It is believed that passers-by discovered her body as smoke poured out of the car from an overheating laptop. She was visiting the Paris area to attend a training course.

Cazeneuve said: "Our thoughts and sorrow are with her relatives, her family, and her daughter now deprived of her presence."

The link between the two is not known.

France increased surveillance of activists posing a potential security risk after the January attacks on the Charlie Hebdo office and a Jewish supermarket.