Hungary has declared a state of emergency in three western counties after a wave of toxic red sludge from an aluminum factory washed through several villages.
Four people, including two children, were killed and around 100 others were injured in what officials have described as the country's worst-ever chemical accident.
Emergency workers were rushing to pour 1,000 tons of plaster into the Marcal River in an attempt to bind the sludge and keep it from flowing on to the Danube, a major European waterway some 80 kilometers away.
Hungarian officials have suggested it will take a year and millions of dollars to clean up the mess. A spokesman for the European Union, Joe Hennon, was quoted by AP as saying that the EU stood ready to help if the disaster took on bigger proportions.
The government said the spill may have been caused by human error and that there was no sign of it being due to natural causes.
The red mud -- waste generated during bauxite refining -- poured out of an open containment reservoir.
Environmental State Secretary Zoltan Illes told national news agency MTI on October 5 that at least 1 million cubic meters of red sludge had spilled from the reservoir.
Army personnel and helicopters were dispatched to help with rescue efforts in the affected area, about 150 kilometers southeast of the capital, Budapest.
compiled from agency reports