MADRID - A Spanish emergency official says an explosion in a new biofuel facility situated near the central city of Salamanca has left one worker injured and caused a fire.

Regional emergency service spokeswoman Marta Marcos says the explosion occurred when a tank of ethanol ignited Wednesday at the plant in Babilafuente, about 20 miles (30 kilometers) east of university city Salamanca.

Marcos says authorities are investigating. The injured worker is in a hospital with minor injuries.

Biofuel differs from normal gasoline in that it is distilled from vegetal plants such as grain or sugar cane.