The number of dogs killed by a mystery toxin in the New Forest has risen to 11.

An investigation is continuing in a bid to discover the source of the poison, which has caused acute kidney failure in dogs that have been exercised at Latchmore Brook, near Fordingbridge.

One of the 12 dogs affected so far survived but the others have all died.

The dog that survived was a four-year-old Jack Russell called Squibby, owned by Henry and Marie-Anne Richardson. She spent nine days on a drip and took weeks to make a full recovery.

New Forest District Council, the Environment Agency and the Forestry Commission have joined forces in a bid to solve the mystery.

A council spokesman said: “There have been no new cases since March 1. However, six further possible cases occurring prior to March 1 have recently come to light, making a total of 12 possible cases to date.

“Environmental and veterinary investigations are continuing and all practical steps are being taken to establish the cause.”

Anyone with any information that could help the investigation is urged to telephone the Forestry Commission spokesman on 023 8028 3141.

The council spokesman added: “Dog owners should be vigilant and contact their vet if they have any concerns about the health of their dogs.”