Updated

A witness says many people have been killed in a mass shooting at a mosque in the New Zealand city of Christchurch.

Police have not described the scale of the Friday shooting but urged people in central Christchurch to stay indoors.

Witness Len Peneha says he saw a man dressed in black enter the Masjid Al Noor mosque and then heard dozens of shots, followed by people running from the mosque in terror.

He says he also saw the gunman flee before emergency services arrived

Peneha says he went into the mosque to try and help: "I saw dead people everywhere."