AN inquiry into how more than 5,000 fish died in an apparently poisoned lake has been launched.

The dead fish at Priory Cottage Lake, Guisborough, Cleveland, include a monster pike of nearly 37lbs, bream to 17lbs and many 30lb-plus carp.

The source of the disaster has not yet been traced by Environmental Agency experts investigating the incident, and Northumbrian Water is also assisting with sampling and testing.

The 900-year-old lake, opposite Butt Lane, was used for centuries by the monks of Gisborough Priory. It is on land owned by Lord Gisborough.

A spokesman for the Environment Agency said: "Samples we have taken indicate the problem may be sewage.

"The problem seems to be isolated to this lake and we are not aware of any spread into nearby water courses."