There are fears that dry weather conditions will cause toxins in the red sludge to be released into the air [Reuters]

Hungary has announced that an aluminium plant behind a toxic spill that killed nine people and left scores injured and homeless has been cleared to start production again.

Gyorgy Bakondi, the country's national disaster chief, said production would resume on Thursday or Friday, as the prime minister visited the area around the plant.

"We have already switched on the industrial heating. As soon as the system has reached its operational temperature level, we will resume production," he said.

The announcement comes a day after the MAL Hungarian Aluminium Production and Trade Company that owned the plant was put under state control, where it will remain for the next two years.

The Hungarian government will freeze the assets of MAL and install its own representative or commissioner at the helm, who will then be responsible for resolving the current catastrophe.

The death toll from the disaster rose to nine on Wednesday as another victim died in hospital after suffering injuries in the toxic flood, the National Disaster Unit said.

Executive freed

Meanwhile, Zoltan Bakonyi, the managing director of MAL who was arrested earlier in the week, has been released from custody, after a judge on Wednesday ruled that prosecutors couldn't substantiate their charges.

Al Jazeer's Anita McNaught, reporting from Devecser, one of the towns nearest to the plant, said that Bakonyi had not yet cleared his name.

"He has been released from police custody. It does not mean that he will not be rearrested or that other directors of the company themselves might be taken in for questioning or indeed charged as a result of that," she said.

Viktor Orban, Hungary's prime minister, has blamed "human negligence" for the spill - which swept over three villages and caused an ecological disaster in a tributary of the Danube River.

The latest checks on the walls of the plant's reservoir have shown no further signs of deterioration, after a local village was evacuated over the weekend due to fears that cracks could lead to another spill.

Tamas Toldi, the mayor of Devecser, said he hopes the state of alert can be called off once a protective wall in neighbouring Kolontar is completed.

Lajos Tolnay, MAL's chairman, said the company would co-operate with an inquiry into what caused the spill but blamed natural causes for the disaster.

In an advance copy of an interview with him in the weekly Figyelo, due to be published on Thursday, he said: "We feel that we are not responsible because our view is that fundamentally it was an unavoidable external force, that is, the development of natural conditions, that caused the catastrophe."

"My colleagues have done everything according to the rules," he added.

'Arsenic in the air'

The Hungarian Academy of Science (HAS) said the heavy metals found in the red mud did not pose a threat.

But it said further checks were needed to determine the full impact of the spill on the soil's ability to sustain life and whether it remained arable. Last Monday's spill affected over 1,000 hectares.

There are concerns over the air quality in the affected areas, with Greenpeace warning that residents could breathe in toxins in the mud if dry weather conditions continue.

"There is a lot of arsenic in the air, there is also arsenic in the soil samples, there is mercury in the soil samples, there is chrome in the soil samples and many other heavy metals are in the soil samples in different concentrations," Jurrien Westerhof, an engineer for Greenpeace, told Reuters.

Source: Al Jazeera and agencies