A stream of passengers departing on foot after a train derailed coming in to Wellington.

Emergency service staff at the scene of a train which derailed near the ferry terminal in Wellington.

Emergency services at the scene of the derailed train.

A spot of pink spray-paint marks where a wheel came off the track.

An exterior view of the damage done to the train carriage.

The damage to the interior of a passenger carriage.

Train services in Wellington have returned to normal following extensive delays caused by a train derailment this morning.

Commuters were squeezed onto reduced train services during peak hour this evening, or moved on to replacement buses to Lower Hutt and Porirua.

Twenty-six Ganz Mavag trains were removed from service after an air reservoir tank for the braking system came off a train coming into Wellington from Porirua early this morning.

NINA WONG OOPS: The interior of the Porirua to Wellington train which derailed.

While the Ganz Mavags were not returned to the tracks this evening, they were expected to operate at full capacity for tomorrow morning's peak services.

The 7.43am train was on its way from Porirua to Wellington when it derailed at 8.14am near the Interislander ferry terminal.

The train was carrying about 350 people who were stranded on the train for about an hour before they were ushered off.

A KiwiRail spokeswoman has confirmed that, as a result, all 26 of its Ganz Mavag units had been taken off the rails for a visual inspection.

That would not be completed by this afternoon’s rush hour, meaning train numbers on some lines would be reduced to running about every 30 minutes instead of up to every 15 minutes. Some other services will be partially replaced by buses.

Check here for any changes to your trip home today

A part that came off the derailed train – and could be seen stuck beneath it this morning – had been raised in a preliminary investigation this morning as an ‘‘area of concern’’ on the Ganz Mavag fleet.

The part was an air reservoir tank that helped the air braking system. Commuters could expect packed trains this afternoon, she said.

It was not clear if the derailed train would be moved by this afternoon but trains would be able to use other tracks.

Related: Bus Services Cancelled For Morning Peak

Four people suffered minor injuries from the derailment, and were treated at the scene.

On a train service caught behind the derailed carriage, a passenger had an unrelated medical emergency and was transported to Wellington Hospital, a Wellington Free Ambulance spokesperson said.

PASSENGER ACCOUNTS

Passenger Zoe Glasson said something came up through the floor of her carriage, cracking it.

"[It was] right next to where a bunch of school kids were standing. They were very lucky not to be hurt."

She said the carriage had been making strange noises since she boarded the train at Takapu Rd station.

"Just before the ferry terminal we heard the noise again but this time it became increasing louder and for the first time the train started moving. It shuddered and vibrated and then jumped up and down violently."

Ms Glasson said it definitely felt like the train could overturn.

"There were passengers screaming. When we came to rest we [were] skewed out from neighbouring carriages sideways, about half a metre."

Seeseei Molimau got on the train at Linden and noticed by Tawa a noise like the carriage was hitting gravel.

‘‘We were hearing it was about to go. Through the tunnel it was running on stones and gravel.’’

After Kaiwharawhara the sound got ‘‘worse and worse’’, she said.

After a loud sound the train derailed and a large round cylinder came up through the carriage floor.

‘‘It wasn’t going too fast, otherwise people would have been in a lot of trouble.’’

‘‘It was flipping scary, it was just so scary.’’

She said it looked like a couple of people had symptoms of whiplash after the train came to an abrupt stop.

Payton Wright was also on the train and said: ‘‘The train started shaking. There were rocks hitting the side of it [the train]. It felt like an earthquake.’’

Fellow passenger Nina Wong said she thought the incident was an earthquake.

"There was debris falling just in front of me and one of the light covers came off ... The shaking lasted for about one to two minutes, getting worse as we kept moving, but then we came to a sudden stop."

Ms Wong said the passengers were told part of the train's wheel had come through the floor, causing it to crack.

On Twitter, Kate Barker said: "I think my train on the Waikanae line has just derailed," then followed with: "Turns out the back carriage has derailed. We're in the middle. Hope the folks at the back are ok!"

She then tweeted to followers: "well there was a lot of screeching and we've come to a holt. Still no word on what's happened."

Were you on the train? Call us on 0800 DOMPOST (0800 366 7672) or email web@dompost.co.nz

KIWIRAIL RESPONSE

Trains are operating on the Waikanae line up to Porirua and on the Hutt line up to Petone.

Buses are replacing all services between Porirua and Wellington and Petone and Wellington.

In a statement KiwiRail’s general manager, oassenger, Deborah Hume said: "A total of nine services were backed up directly behind the train. We are also in the process of evacuating passengers on these trains and transporting them by bus to Wellington Station.

"Our first priority is to ensure our passengers can safely evacuate the trains. In order to do this, we have shut off power to network around the area.

KiwiRail and the Transport Accident Investigation Commission would all launch investigations into the accident.

No timeframe for clearing the scene has yet been given.