Watch: Wellington motorist boards bus after crash, rages at driver, passengers

Video has been posted to social media showing a heated altercation between a Wellington motorist and a bus driver after a collision near the CBD.

The footage, posted to a Wellington Facebook page, shows the fight between the driver of a car and a bus-load full of passengers.

Tahila Reardon-Arnold was on board the Wellington bus traveling from Newtown into Wellington CBD when the incident occurred.

"We were stopped at the lights, and when the bus started driving, a car merged into the bus lane and hit the side of the bus."

Ms Reardon-Arnold didn't believe that the bus driver was in the wrong.

"We all felt it and heard it... bits had fallen off the guy's car."

The driver of the car leapt out of his vehicle and started videoing the damage done to his car.

"The bus driver got out, and the driver of the car started an argument outside. I think he was trying to get a reaction out of the bus driver."

When Ms Reardon-Arnold saw the driver of the car was filming his altercation with the bus driver, she thought she should do the same.

"I was with my son [and] he's only a baby - I felt safe because there were lots of people on the bus, but I did feel quite scared for the bus driver."

At that point, the driver of the car boards the bus, and can be seen yelling that he knows the bus driver was in the wrong because he's a bus driver himself.

"I drive things as big as well," he said.

The man then turns to the passengers of the bus to defend himself, saying he is still in the lane he tried to merge into.

One passenger then refutes that, telling him, "You're not in the lane, mate - you're in the middle of the road."

Ms Reardon-Arnold said the driver then ran over to the bus driver's steering wheel, which alarmed some passengers.

"I think he was trying to find out the bus driver's name, but the bus driver kept telling him to move away from his wheel."

Newshub has not been able to confirm whether the driver of the car is also a bus driver.

Newshub spoke to passengers who said they were considering reporting the incident to the authorities, but Wellington Police says no complaint about the incident has been filed.

A bus company and Greater Wellington Regional Council have been approached for comment, but have not responded.