Hungary has declared a state of emergency in three counties. On Monday, a torrent of toxic red sludge from an alumina plant reservoir, tore through villages, killing four and injuring 120.

The toxic red sludge engulfed several towns. People trapped in its path were burned. Four of the victims died, six are missing and at least 120 people are injured.

Hundreds of tons of plaster were poured into the Marcal River to bind the toxic sludge and prevent it from flowing on.

Hungary's Environmental Affairs State Secretary says about one-million cubic meters of sludge leaked from the reservoir, affecting an estimated 40 square kilometers.

He says the flood is an "ecological catastrophe" that could eventually reach the Raba and Danube rivers. Activity is suspended at the plant and the company was ordered to repair the damaged reservoir.

Environment Affairs State Secreatary Zoltan Illes said, "We have ordered MAL to make plans and start reconstruction work. If they don't launch these projects, they will face serious consequences."

Nearly 400 residents were evacuated and 110 were rescued from the flooded towns. Hungarian Prime Minister Viktor Orban says the sludge spill may have been caused by human error, but there was no threat of radiation in the flooded areas.