It happened on the River Mole near South Molton
A formal investigation is underway after the pollution incident.
The Environment Agency says the pollutant has been identified as anaerobic digestate.
A 5 kilometer stretch of the the river was impacted and they've calculated that 10,000 fish died.
They say they can't share any further details at this time.
Dartmoor visitor centre gets one last reprieve
But it will close in October unless cash can be found
Cornwall is key to Torbay's role in Devon devolution
'The two counties are natural partners'
Devon and Cornwall should combine under mayor, says Exeter MP
Steve Race supports city's unitary bid too
Plymouth supports South West Peninsula authority
Counties will get more working together, its claimed
Devon votes in favour of postponing May’s elections
Claims of democracy ‘denied’
