Undersea quake hits Indonesia

A powerful undersea earthquake struck the Indonesian island of Nias yesterday, causing widespread panic.

The quake measured an estimated 6.3 and struck about 220km out to sea southwest of the city of Medan at 4.44am NZ time, the Hong Kong Observatory said.

It cut off the city's electricity supply and caused widespread panic for residents.

Many ran for the hills clutching their babies, an AFP correspondent said.