Police in Christchurch are seeking witnesses to the aggravated robbery of a taxi driver.
They say two men threatened to kill the First Direct taxi driver with a knife after they were picked up in the suburb of Shirley on Sunday morning.
The men, thought to be in their 20s, grabbed the driver around the throat and hit him hard on the back of his head, causing him to crash into trees in the suburb of Redwood.
The driver told police the men appeared to have been drinking and were wearing peaked caps.
The driver was very shaken by the incident. He suffered concussion and has a sore head and neck.
The New Zealand Taxi Federation says the aggravated robbery reinforces the need for compulsory security measures in taxis.
Executive director Tim Reddish says it is fortunate the driver was not seriously injured and the sooner sooner security cameras are introduced, the better.
In March Transport Minister Steve Joyce announced that security cameras would be compulsory in taxis by the end of this year.
