A vast fire and huge plumes of dense black smoke at Spain’s largest car tire dump has two regions on alert.

The blaze started in the early hours of Friday at the controversial and illegal tire cemetery, which had been attracting criticism from environmental groups and residents for years.

The dump is located in Seseña, a new town some 36 kilometers southwest of Madrid that is also partly within Castilla-La Mancha. Both regional governments issued a Level 1 alert, and school children were sent home in Seseña. Later on Friday afternoon residents from the El Quiñón de Seseña housing development were also evacuated from their properties, due to the risk from the fumes. Around 9,000 people live in the apartments.

Alert raised

At around 1.30pm on Friday, Castilla-La Mancha raised the alert level to 2.

“This will allow water aircraft to drop large amounts of water from above and put out the fire faster. At this point we had two options: let the fire burn all the tires or think about the environment and prevent the flames from spreading. We chose the second option,” said regional premier Emiliano García-Page, who has traveled to the site of the blaze.

We recommend that people in nearby areas keep their doors and windows shut to avoid exposure

Luis Villarroel, chief regional firefighter

García-Page added that the effort will require several days because there are an estimated five million tires at the dump. He also said that the army is on standby in case its help should be required.

Arson suspected

Authorities are still trying to determine the cause of the blaze, but are increasingly thinking that it might have been deliberate.

“I've been talking with the two workers at the gas station who raised the alarm, and they told me that the fire started on one side of the dump, which makes us think it was not a random occurrence that could have happened in the central portion,” said García-Page. “Besides, it was not so hot last night as all that. But for now we are not drawing any conclusions.”

Stay indoors

Ten firefighter units from Madrid and Toledo are working with heavy machinery to put out the fire. Luis Villarroel, chief of the regional firefighting force, said that around a fifth of the thousands of tons of accumulated tires are burning.

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“We are now focusing on preventing the fire from extending to other areas,” he said. “We recommend that people in nearby areas keep their doors and windows shut to avoid exposure.”

The dump contains an estimated five million discarded tires spread over 9.8 hectares of land. So far, one hectare is affected by the flames.

“We’re okay at school, it doesn’t smell like smoke. But we have to remain vigilant,” said Marta Fernández, a primary school teacher in the nearby municipality of Valdemoro.

Authorities have asked residents to reduce their exposure to the smoke and to close their doors and windows. All schools in Seseña have suspended classes and the local police are telling people to stay indoors, especially if they have respiratory problems.

The town of Seseña was already notorious for a massive residential development that stood empty for years and came to symbolize the excesses of the Spanish real estate boom. Meanwhile, the tire dump was declared illegal in 2003 for failing to meet environmental requirements.