Three people were in hospital after crash between a Glider bus and a car in Belfast.
The incident happened at around 11.30am on Wednesday close to the Holywood Arches as the bus made its way toward the city centre.
Police said they are investigating after the bus and a black Peugeot car collided.
One regular Glider commuter said his wife was on the bus at the time with their young child.
The man - who asked not to be named - claimed six people were injured with some left lying on the floor. Some had blood on their faces and one man said he was feeling dizzy.
Police said two men and a woman were taken to hospital after the incident with injuries not thought to be life threatening.
The man said he felt there were safety concerns over the lack of seats on the Glider buses.
They are designed to have more standing room than seats in order to create a tram-like on-off ability and to carry more passengers.
"I miss the bus," the man told the Belfast Telegraph.
"The Glider is standing room only. They market it like a tram but they should have just built a tram.
"The Glider is always packed. For me to have so many people standing and the vehicle having to react to what other drivers are doing on busy roads is a safety issue.
"While they may not have got enough people on the old bus, at least there was a seat for almost everybody on board."
Translink said the buses met the highest safety standards and was investigating the crash.
The Glider provides a service from east to west across the city with links to the Titanic quarter. The £90million scheme was launched in September 2018 after extensive work on resurfacing roads and installing specific stops.
In its first year Translink said it carried over two million more people in its first year compared to the bus services it replaced.
A spokeswoman added: “We can confirm there was an incident involving a Glider travelling in east Belfast at approximately 11.40am this morning.
“Emergency services were called to the scene and three passengers were taken to hospital.
“We have launched a full investigation."
She continued: "It is a common design of rapid transit systems that space is provided for standing passengers. This allows greater capacity, especially during peak periods.
“The Glider vehicles meet both British and European safety standards, and are in common use throughout Europe".
The ambulance service said two emergency crews were dispatched to the scene with patients taken to the Royal and Ulster hospitals.
Police said they received a report of a two-vehicle crash at 11.50am on the Upper Newtownards Road on Wednesday. They have appealed for anyone with information to contact police on 101 quoting reference number 610 13/11/119.