7 August 2012 Last updated at 09:58 ET

Drayton Reservoir fish death: Further test being carried out

Further tests are being carried out at a popular fishing reservoir in Northamptonshire where hundreds of fish have been found dead.

Up to 1,200 roach were found dead last week at Drayton Reservoir near Daventry but the numbers are still rising.

A full set of tests were carried out by the Environment Agency last week but the cause is unknown.

The Canal and River Trust said this was the first time that large numbers fish had been found dead at the reservoir.

Bacterial infection

John Ellis, national fisheries and angling manager at the trust, said: "The water was tested for pollution but the results came back all clear.

"We are still waiting for results for tests for viruses and bacteria which will take about two week to come back."

Mr Ellis added: "It could be that spawning started but was not completed because the weather was hot and then cold. This could cause a bacterial infection in the fish."

The Environment Agency said: "The fish seem to have died some time before we were asked to take samples and water quality tests and some tests on dead fish have shown nothing obvious as a cause.

"It is possible that the roach could have died a while back and then took some time to rise to the surface."

Drayton Reservoir is a popular fishing spot for anglers. It is known for the large numbers of Carp in the waters which can be between 12lbs and 14lbs in weight.

The Environment Agency said it expects more results in two or three weeks.