Beavers have been born in Britain for first time in 400 years - on an exclusive housing development.

The 12 kits are flourishing at the 550-acre Lower Mill Estate near Cirencester, Gloucestershire - a sustainable luxury home complex designed by 30 of the world's top architects.

Experts believed six beavers introduced there three years ago had bred in January, after noticing tell-tale signs. But no-one had seen the kits until now.

Lower Mill Estate owner Jeremy Paxton brought three pairs - called Tony and Cherie, Gordon and Sarah, John and Pauline - to Flagham Fen Lake in 2005. Beavers were hunted to extinction in the 16th century because their throat glands were thought to be medicinal.

Developer Jeremy Paxton said: "Beaver kits can swim, but it may take them a month or more to figure out how to hold their breath and swim underwater. When they get tired, they catch a ride on their mother's back. Lower Mill residents hope to witness all this activity and more, yards from human habitation.