The Hungarian village close to a damaged reservoir, which sent alumina sludge tearing through the area earlier this week, is being evacuated due to fears about its dam, a spokesman for disaster crews said.
Spokesman Tibor Dobson said that the dam of the damaged part of the reservoir has further weakened, and disaster crews have decided to evacuate 800 people from the village of Kolontar as a precaution.
Prime Minister Viktor Orban had just arrived at the village.
Disaster crews are also preparing to evacuate nearby Devecser as well if necessary.
Hungary declared a state of emergency in three counties on Tuesday after toxic sludge from an alumina plant flooded three villages on Monday about 100 miles west of Budapest, killing seven people and injuring around 150.