On October 4, 2010 at 12:30 the western dam of cassette X of the sludge reservoir, owned by Magyar Alumínium ZRt (Hungarian Aluminum Co), had ruptured. Due to the ruptured dam, a mixture of 600-700 thousand m3 of red sludge and water inundated the lower sections of the settlements of Kolontár, Devecser and Somlóvásárhely via the Torna creek.
The sludge flood reached 40 residential properties and 2 municipality-owned buildings in two streets of Kolontár, as well as 244 residential properties in 19 streets of Devecser and 14 residential properties in Somlóvásárhely. According to the helicopter survey, 3 hectares were directly flooded with sludge in Kolontár and 7 hectares in Devecser.
Immediately after the event 4 people (a man aged 37, a woman aged 73, a woman aged 82 and a little girl aged 14 months) were found dead by rescue units. Cause of death in all 4 cases was drowning. There is an ongoing search for 3 missing persons (two women aged 76 and 85 and a man aged 73 years).
The number of people injured in the industrial disaster and hospitalised is 123, out of whom 12 are considered to be in a serious condition.
During the recovery operation 8 fire-fighters, 1 soldier and 8 policemen suffered first- and second-degree burns or respiratory tract injuries. Out of the injured personnel, 4 fire-fighters and 8 policemen were taken to hospital and discharged the same day after receiving treatment. There are 64 patients currently receiving hospital treatment.
As of October 9, the number of deceased victims stands at 7; the search continues for 1 missing person.