Hong Kong Protests: Thousands surround police headquarters

Thousands of people in Hong Kong have surrounded police headquarters, calling for an extradition bill to be scrapped.

Police have asked the protesters to withdraw peacefully, saying their presence would seriously affect emergency services.

In recent weeks, millions of people have marched against the bill, with violent clashes breaking out with police.

The bill, which allows extradition to Mainland China, has already been suspended.

Critics say it would erode the judicial independence of Hong Kong.

Since 1997, Hong Kong has been part of China under the one country, two systems principle.