MADRID • The head of Portugal's league of firefighters said on Wednesday he believed arsonists had most likely started the fire that killed 64 people last weekend, contradicting a police assessment that attributed the cause to lightning.

The claim is certain to increase concern about misinformation by the authorities during a tragedy that has traumatised the country.

It comes a day after Prime Minister Antonio Costa ordered an investigation into possible flaws in the emergency response, including why motorists were allowed to drive into the fire that they had sought to escape. Most of the fire victims died on the road, stranded in their cars.

On Wednesday, Mr Jaime Marta Soares, president of the Portuguese Firefighters League, told TSF, a Portuguese radio station, that he was convinced the fire was provoked by "a criminal hand".

He suggested that lightning struck about two hours after the fire had already begun, but did not offer evidence to back his claim.

On Sunday, a day after the fire began and as firefighters scrambled to reach isolated hamlets in the burning forest in the central Pedrogao Grande region, Mr Jose Maria de Almeida Rodrigues, the national director of Portugal's judicial police, said the fire "very clearly" was a result of natural causes.

At the time, the police chief said officials had identified the exact spot in the forest where lightning first struck during a so-called dry thunderstorm, in which there is lightning but no rainfall.

Yesterday, the civil protection agency said the main forest fires were brought under control.

The debate over the fire's origins comes after Portugal completed on Tuesday three days of mourning for victims of the tragedy, during which politicians mostly heeded a call by President Marcelo Rebelo de Sousa to deal with the emergency first before discussing its circumstances. However, it is now likely that the fire will turn into a political and institutional confrontation.

Environmentalists want the disaster to serve as a catalyst for politicians to address long-standing problems relating to the mismanagement and neglect of forests.

The migration of rural people to cities and coastal areas as part of the country's economic development has also left vast amounts of farmland dangerously untended.

While the authorities have yet to identify all 64 victims, the number of injured was raised to 204 on Wednesday, more than triple the number announced last weekend .

The government said it would create a fund to finance the reconstruction of devastated villages and help support residents in a thinly populated farming area that has become increasingly reliant on tourists.

NYTIMES, AGENCE FRANCE-PRESSE