Criminal negligence inquiry into Hungary sludge spill
Police in Hungary have opened a criminal negligence inquiry after leaking chemical sludge caused the country's worst ecological disaster.
Hungary says it will take at least a year to clean up the red mud from an alumina plant reservoir in the western county of Veszprem.
Four people died and at least 120 needed medical treatment, while three are still missing.
The EU fears the sludge may seep across Hungary's borders via the Danube.
"We're concerned not just for the environment in Hungary but this potentially crosses borders," EU spokesman Joe Hennon said.
The Danube river flows through Croatia, Serbia, Romania, Bulgaria, Ukraine and Moldova before emptying into the Black Sea.
Hungary's disaster management agency regards the sludge - a mixture of water and mining waste containing heavy metals - as hazardous.
Its victims are believed to have drowned, with the depth of the fast-moving flood reaching 2m (6.5ft) in places, but many of those injured had suffered chemical burns.
The reservoir near the village of Kolontar was no longer leaking as of Wednesday.
'Polluted and destroyed'
Some 600,000-700,000 cubic metres (21m-24m cubic feet) of sludge gushed from the Ajkai Timfoldgyar plant in Ajka, 160km (100 miles) from Budapest, on Monday.
It affected some 40 sq km (15.4 sq miles) of mainly agricultural land, engulfing several villages.
National Police Chief Jozsef Hatala said Hungary's national bureau of investigation (MNY) would lead the investigation "given the complexity and importance of the matter".
MAL Rt, the Hungarian company which owns the plant, said earlier there had been no sign of the impending disaster and the last examination of the reservoir pond on Monday had shown nothing untoward.
It also argued that, by EU standards, the sludge had not been considered hazardous.
Hungarian Prime Minister Viktor Orban was quoted by AP as saying the plant and reservoir had been inspected only two weeks earlier and no irregularities had been found.
Herwit Schuster, a spokesman for Greenpeace International, described the spill as "one of the top three environmental disasters in Europe in the last 20 or 30 years".
Land had been "polluted and destroyed for a long time", he told AP.
"If there are substances like arsenic and mercury, that would affect river systems and ground water on long-term basis," he added.
Janosne Stumpe, 76, suffered chemical burns to her legs.
She told AFP news agency of literally having to cling on for dear life when a 2m wave of sludge bore down on her home as she was tending her pigs in Kolontar.
"My son said the end was coming, and I thought it was too," she said.
"I quickly jumped on a case, but the flood washed it out from under me so I grabbed the roof beams [of the pigsty] and I was hanging there until the rush went away."
Her son, she added, was "still in hospital with very, very serious burns".
Janos Zlinszky, from Hungary's environmental watchdog, told BBC World Service the impact of the spill on the countryside was striking.
"It's like when you paint a landscape red," he said.
"It's really incredible. I mean, for kilometres wide, there is like a huge paintbrush. If you take a map and with a big paintbrush, just draw a zigzag line through it."