Signs of life in quake damaged building - NZ rescue official
"We have an active operation underway at the moment to try and ascertain what's happening," fire rescue official Jim Stuart Black told TV3.
No survivors have been found since mid-afternoon Wednesday.
The force 6.3 quake struck the city early afternoon on Tuesday.
Seventy one people are confirmed dead but the toll is expected to rise.
(Created by Gyles Beckford)