At least four people were injured and another 600 were evacuated when a gas truck exploded Tuesday at a gas station in the coastal Chilean city of Viña del Mar, authorities said.

The accident occurred soon after 12:30 p.m. when the truck was unloading gas at the station.

The truck had a gas leak that caused it to explode and ignite the fire, witnesses told Radio Cooperativa.

Police immediately cordoned of a perimeter three blocks from the station, while firefighters tried to control the blaze and keep it from spreading to neighboring homes, businesses and a nursery school.

Authorities ordered the immediate evacuation of all nearby buildings, which had some 600 people inside them, police Gen. Julio Pineda told CNN Chile.

"There's a risk of explosions since there's still gas in the truck and temperatures are very high," the officer said, adding that traffic around the perimeter was totally blocked.

About the injured, he said that one of them was the truckdriver and all were taken to nearby hospitals. EFE