Residents of five north-eastern towns in Spain were ordered to stay indoors for two hours after a chemical explosion at a warehouse spread a large, orange toxic cloud over the area.

Residents warned to stay indoors in Spanish towns.

Residents warned to stay indoors in Spanish towns. Image by AP Photo/Manu Fernandez

The blast occurred when products being delivered to a warehouse in the city of Igualada became mixed, exploded and set a truck on fire, according to a spokeswoman for Catalonia’s regional fire service. She said two people were slightly injured. Firefighters said the chemicals were nitric acid and ferric chloride.

The cloud came from an explosion after an accident in a warehouse.

The cloud came from an explosion after an accident in a warehouse. Image by AP Photo/Manu Fernandez

The region’s civil protection department ordered some 65,000 residents of Igualada and four nearby towns to stay indoors until the cloud dissipated. The order was lifted two hours later but maintained for pregnant women, children, elderly people and those with respiratory problems.

Roads in and out of Igualada, located some 40 miles north-west of Barcelona, were cordoned off during the alert and people were urged not to place themselves in danger by taking photographs of the cloud.

(Press Association)