New radioactive leak at Japan's Fukushima nuclear plant

Japan's crippled Fukushima nuclear plant has a new leak of radioactive water after its workers miscalculated and overfilled a storage tank, says its operator Tepco.

As many as 430 litres (100 galloons) of water may have leaked from the tank, possibly flowing into the sea.

Tepco has struggled to deal with the huge volumes of contaminated water since the nuclear facility was badly damaged by an earthquake and tsunami in 2011.