Hundreds of people have been evacuated from a town in Hungary amid threats of a second spill of toxic red sludge.
Authorities say the wall of a damaged industrial reservoir is likely to completely collapse.
About a million cubic metres of waste leaked out of the alumina plant earlier this week, killing seven people and injuring dozens more. The new evacuations are from the town of Kolantar, hard hit by the initial leak.
Officials say a further 500,000 cubic metres of even thicker sludge could be spilt because of the weakened walls of the reservoir.
Most of the water life in the Marcal River reportedly died after the spill, and dead fish have been seen in other rivers.
So far, though, experts say there are no reports of any serious damage to the main branch of the Danube. The government is promising a full inquiry.