Environment chiefs have warned pet owners not to go out on frozen streams, rivers and ponds to retrieve straying dogs.

With a slight thaw forecast for Sussex over the next few days, venturing on to any frozen stretch of water would be particularly foolhardy, the Environment Agency said.

Dogs, which are equally at risk from drowning as their owners, should be kept on leads near icy streams and ponds.

The agency said drivers should be careful when parking beside rivers and lakes because the combination of cold nights and daytime sunshine increases the risk of cars sliding in.

A spokesman said: "We are concerned that an accident on the ice could turn a winter wonderland into a place of tragedy.

"Anyone walking or driving near rivers, ponds or lakes should exercise extreme caution."