The Environment Agency has identified the source of an oil leak in the River Yare.

The oil has been seen along the River Yare close to the University of East Anglia at Colney.

Officers have been trying to trace the site which has seen oil flowing down the river intermittently since at least December 22, when the Environment Agency was first informed of the issue.

Now nearly three weeks since investigations were launched, an Environment Agency spokesman said a likely site has been identified and it was working with the owner to ensure no further oil is released.

A spokesperson from the Environment Agency said: “Our officers are continuing to respond to an incident involving pollution of the River Yare at Colney in Norwich.

“Oil has been intermittently coming out of a drain near Chancellors Drive which takes surface water drainage from a large area around the hospital and research park, and across to the A47. Following extensive enquiries, we have identified the likely source of this oil and are working with the site owner to ensure no further oil is released and the spill site and surrounding drains are remediated.

“We continue to monitor the outfall and the containment measures will remain in place in the river to collect any residual oil which may be released from the drain.

“No fish or wildlife appear to have been affected, but we will continue to monitor the situation closely.

“Dog walkers are advised to keep their pets out of the water and swimmers should stay away from any polluted stretches.”

Since the first reports before Christmas, booms were put in place to control the issue and dog walkers asked to keep their pets away from the river.

Oil has been seen on the River Yare as far downstream as Lakenham, but the Environment Agency said there is "no evidence that the UEA lake has been affected".

UEA researchers Dr Iain Barr and Professor Ben Garrod previously highlighted concerns over the "irreparable damage" to fragile habitats.

Dr Barr said: "People at the UEA are concerned there can be an adequate assessment of the impact of this. Diesel still coats the vegetation along the sensitive river. You have the Norfolk hawker which is on the rarest species found in that space. What difference will this have? What is the next steps. There needs to be a clean up."