NZ launches war on rats

The authorities in New Zealand have dropped more than 100 tonnes of poisoned bait on a remote island near the Antarctic to try to rid it of rats.

Organisers say it's the largest pest control operation of its kind ever undertaken.

The aim is to kill the estimated 200,000 rats on Campbell Island, which are thought to be harming the area's wildlife.

The island is about 700km south of New Zealand.

Wildlife experts believe the rats were introduced on whaling ships in the 19th Century.

From the newsroom of the BBC World Service