Large meteor fragment lands in Russia lake, say police

A large fragment from a meteor that crashed in Russia has landed in an icy lake, police say.

Scientists are keen to analyse the remnants, found near Chebarkul, a town in Chelyabinsk region.

The Russian Academy of Sciences estimates that the meteor weighed about 10 tonnes and entered the Earth's atmosphere at a speed of at least 54,000 km/h (33,000mph).

As BBC science reporter Rebecca Morelle explains, most of the meteor would have burnt up before hitting the ground.