Sainte-Maxime, France ? Forest fires swept through parts of the ritzy French Riviera for a second day Tuesday, devastating scenic woods and forcing thousands to be evacuated. At least four people have been killed.

Authorities speculated that the blazes — some 30 broke out nearly simultaneously on Monday — were caused by arson. Molotov cocktails were found in the region, local officials said.

Firefighters met with some success battling the fires near the western portion of the French Riviera, but at least one re-erupted Tuesday east of Draguignan, about 30 miles from the fashionable resort of Cannes, which was untouched.

Forest fires frequently devastate wide swaths of the Riviera back country during the summer. But the blazes that broke out Monday were described as the worst in the southern Var region in decades.

Clouds of yellow and gray smoke blew across the skyline of the area, about halfway between Toulon and Nice.

Thick with Mediterranean pine trees and picturesque bays, the region is a magnet for tourists and a favorite of painters.

About 60 homes were destroyed or damaged as flames ripped through some 21,000 acres by Tuesday morning.

Police in Draguignan said they had detained a 30-year-old municipal employee from the nearby village of Figanieres, who was suspected of having started several fires. More details were not available.

Police officers escort a couple to identify what used to be their car at the Colombier camping site in Frejus, southern France. About 30 fires broke out almost simultaneously Monday evening and raged through nearly 20,000 acres of some of the most prized vacation areas in the Var region.