Firefighters who waded into the 20ft-deep (6m) pond at Newbold in Chesterfield, Derbyshire, to try to rescue the boys, aged 12 and 13, were beaten back by the cold and were treated for hypothermia at Chesterfield and North Derbyshire Royal Hospital. Police frogmen recovered the bodies.
Elsewhere, seven people were injured, one seriously, in a nine- vehicle pile-up on the M6 near Tabley in Cheshire due to tyre debris on the road. The accident occurred hours after police advised motorists to stay at home.
London Weather Centre has warned that fog and frost will continue to cause problems on the roads today, blighting much of England and Wales.
Freezing fog patches are expected to leave roads icy again today, especially in the Midlands, Vale of York and the South-east.
Police throughout the North, North-east, South and Midlands have once again urged drivers not to travel unless absolutely necessary.
Night temperatures are expected to drop below zero over most of the country, falling as low as -5C (23F) in the Midlands.