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A loud explosion has been heard around Bishopdale Mall in northwest of Christchurch.
The mall was cordoned off by police after a man went into Westpac Bank in the mall demanding money at around 1.30pm.
Police say he left a suspicious looking bag before leaving the bank.
The bomb disposal squad and a Customs bomb dog unit are at the scene, where there is also a heavy police presence.
There has been a loud explosion, which may have been the bomb squad exploding the bag and its contents, said Newstalk ZB host Ali Jones, who was at the scene.
Police say there have been no arrests and it is not yet known if money was taken from the bank.
- NEWSTALK ZB
