PARIS, Jan 12 (Reuters) - French sugar and ethanol maker Tereos was ordered to pay more than 9.5 million euros ($10.2 million) on Thursday for polluting in 2020 a river that flows from France to Belgium, killing thousands of fish, the company said.

A leak had been found in a 100,000 cubic metre settling pond at Tereos' factory in Escaudoeuvres in northern France, which led to the spill of waste water into a tributary of the Scheldt river, also known as the Escaut.

"We have our share of responsibility as a company but we regret that the court did not take into account the fact that there was a multitude of causalities and responsibilities," a Tereos spokesperson said.

Authorities in the Belgian region of Wallonia had said 50-70 tonnes of fish died in its territory along a 36 km (22 mile) stretch of the Scheldt and also accused the French authorities of being too slow to issue a warning.

About 13 tonnes of dead fish were also found on the French side of the border.

The criminal court in Lille, northern France ordered a fine of 500,000 euros and more than 9 million euros in damages, of which nearly 9 million for Wallonia, the Tereos spokesperson said, adding the group had not yet decided whether it would appeal the decision.

Sugar beet residues are rich in organic matter and can drive down oxygen levels in rivers.

($1 = 0.9287 euros)

(This story has been corrected in the third paragraph to say 'causalities', not 'casualties', and add the name of the court in the sixth paragraph)

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