Meltdown alert at Japan reactor

Technicians are battling to stabilise a third reactor at a quake-stricken Japanese nuclear plant, which has been rocked by a second blast in three days.

The fuel rods inside reactor 2 at the Fukushima Daiichi plant have been fully exposed on two separate occasions, raising fears of a meltdown.
Sea water is being pumped into the reactor to try to prevent overheating.
A cooling system breakdown preceded explosions at the plant's reactor 3 on Monday and reactor 1 on Saturday.
The latest hydrogen blast injured 11 people, one of them seriously. It was felt 40km (25 miles) away and sent a huge column of smoke into the air.
The outer building around the reactor was largely destroyed.But as with the first explosion, Tokyo Electric Power Company (Tepco) said the thick containment walls shielding the reactor cores remained intact. It also said radiation levels outside were still within legal limits.