Police are deeply concerned after an Auckland taxi driver was found driving allegedly six times the legal breath alcohol limit.
The driver was working at the time.
Auckland Motorways staff responded to a driving complaint on the South-Western Motorway (SH20) after 2pm on Thursday.
"The taxi van was heading northbound, and another motorist called us reporting the driver had been potentially falling asleep at the wheel," Senior Sergeant Bill Russell, Auckland Motorways, says.
"While speaking with the call taker, the caller advised the taxi van had several near misses with other motorists on the road."
As the taxi van neared the Waterview Tunnel, its speed continued to fluctuate between slower and higher speeds.
Motorways units located the van on SH20 near the Mount Albert area.
The 40-year-old male driver was taken into custody for breach alcohol procedures.
Alarmingly, he allegedly returned a result more than six times the legal limit (250mcg).
"It's deeply concerning to us that a professional driver has been transporting passengers while allegedly under the influence of alcohol," Senior Sergeant Russell says.
"I shudder to think what might have happened had this man not been stopped."
Senior Sergeant Russsell is praising the actions of the initial caller.
"The person that reported this to us should be commended for seeing something and doing something about it, calling Police.
"I understand the caller also got behind the van and put hazard lights on to try and warn other motorists, and we acknowledge their assistance."
At this stage the driver has been summonsed to court on a charge of being a transport service driver with breath alcohol over 400mcgs per litre.
Police enquiries are ongoing and further action cannot be ruled out.