Sonali explains nuclear power
There have been two explosions at a nuclear power plant in Japan which was damaged in Friday's earthquake.
Experts are battling to stop a third reactor from exploding, and are pumping seawater in to try to cool it down.
Thousands of people have been evacuated from the area. Officials say there is a low chance of dangerous radiation leaking out.
The most recent blast injured 11 people and sent a huge column of smoke billowing into the air.
WATCH: Latest Japan devastation
A massive rescue operation is underway to find the thousands of people missing after the quake and tsunami which followed.
Japan has also been hit by a number of powerful aftershocks, which are smaller earthquakes which follow a major one.