People are being warned after blue-green algea has been found at a popular nature reserve. 

Thetford Forest is warning people and dog owners after the discovery was made at Lynford Water. 

A spokesman for the nature reserve said bacteria and algea levels can fluctuate in lakes and ponds. 

"This is a natural process dependent upon environmental conditions," the spokesman added.

"Some people and dogs are more sensitive to these changes, and particularly during hot and dry weather spells exposure may lead to symptoms such as upset stomachs and skin irritations.

"Users in or around the water should assess the conditions, their own or pet’s health and their judgement before interacting with the water."