A graffiti attack on an Auckland train by a group of taggers in black masks has highlighted how transport staff could work better with police, an independent report has found.
The gang of 12 hijacked the Britomart-bound train in broad daylight at Avondale's Baldwin Ave station on September 17, 2017.
The driver had been slowing for the station when he noticed the "suspicious" gang approaching in masks and decided he would keep the doors closed to protect passengers.
However, before the train stopped, one of the group jogged alongside and pulled an emergency door release lever on the outside of one carriage.
Two others also pulled emergency releases on separate carriages - effectively immobilising the train.
The gang then spray-painted a giant graffiti image along the entire "platform side of the train", with one member recording the incident.
The driver instructed passengers to stay on the train to avoid a confrontation with the gang and contacted "train control" and the operations centre of contractor Transdev, which operates Auckland's passenger trains.
Passengers also phoned the emergency 111 line to police.
The gang spent seven minutes spraying the train before scampering away along the rail line towards Mt Albert.
No one was injured and staff shortly afterwards disembarked passengers on to the station platform to await the next train, before taking the train to the Wiri maintenance depot.
A Transport Accident Investigation Commission report found the design of the train's emergency door release levers met industry standards by achieving a balance in deterring unauthorised use while still being accessible in emergencies.
Transdev staff also acted appropriately in the situation, the commission report found.
However, the response to the incident could have been "more efficient" if the train's crew had immediately called police.
The commission also found Transdev had no policies or procedures in place to guide train crews in how to deal with "unusual" situations like this.
The commission therefore recommended Transdev improve the training given to train crews, including liaising with emergency services in unusual incidents.
"A key lesson arising from the inquiry is that in any emergency situation, it is important that clear, concise and timely information be given to first responders so that a fast and efficient response can be planned and executed," the commission report concluded.
Transdev said in a statement it was changing its training procedures in response to the commission's report.
"Train managers will be asked to contact emergency services directly," it said.
"At the time of the incident, KiwiRail's procedures required train managers to communicate through drivers. KiwiRail, as the network access provider, sets many of Transdev's operating procedures."
Transdev said it has always had an "extensive training programme" and because of this training the train crew kept the carriage doors closed, meaning "passengers were never at any risk from the incident".
Auckland councillor John Watson was a passenger on the train in 2017 and told the Herald at the time he watched as the gang raced towards the carriages in "ninja" masks.
"They were sprinting to get to the part of the train that they were assigned to do."
He said passengers became distressed during the incident because they felt locked into the train and some "were banging on the walls and windows to get out".
"The public were imprisoned while they did their stuff, you're like a hostage for 10 minutes," Watson said.
"People inside were getting affected by the fumes, struggling for fresh air."