Toxic sludge reaches Danube river, eco disaster spreading outside Hungary

Officials from several nations along the Danube, downstream from Hungary - Croatia, Serbia and Romania - have been testing the river on Thursday, hoping that the river's huge water volume would blunt the impact of the Hungarian red toxic sludge spill. Europe's second longest river, Danube flows through Croatia, Serbia, Romania, Bulgaria, Ukraine and Moldova before emptying into the Black Sea.

The toxic sludge burst out of a metals plant reservoir and flooded three villages in Western Hungary, killing at least four people, injuring 120 and leaving three missing. It reached the mighty river Danube on Thursday, but a Hungarian emergency official said no immediate damage was evident. Experts are expecting contamination levels to peak over the weekend.