TESTING is under way at Hinksey Stream this morning after dead fish were discovered in the water.

A canoeist raised the alarm yesterday while paddling down the section next to the Fishes pub. The pub has not been linked with the incident.

Officials from the Environment Agency and Thames Water were called and a black substance was seen in the stream at about 10pm.

The source is not yet known but staff from Thames Water said the stream had now been deemed safe. Six dead fish have been discovered, however.

They remain at the riverbank this morning and have continued their tests.

A Thames Water spokeswoman said: "The Environment Agency asked us to help with their investigations yesterday after a small number of dead fish were seen in the stream.

"So far there is no sign of any sewage in the water or issues with our pipes in the area, however we’re continuing to support the EA with their ongoing work today."