Five buses crashed in Manchester city centre on Thursday morning, causing havoc during rush hour and injuring 15 people.
The collision occurred at around 8.15am, and the roads around Piccadilly ground to a halt in the aftermath, reports ITV News.
The crash involved Arriva, Stagecoach and Magic buses on Portland Street, between Chorlton Street and Minshull Street.
Investigators believe a broken accelerator pedal could have caused an Arriva bus to career into four other buses at high speed as it was pulling out of Picadilly Gardens bus station, reports the Manchester Evening News.
One passenger, Dariya, 19, was going to work on the number 86 Stagecoach. She told the Manchester Evening News: "We were arriving at Piccadilly and we saw an Arriva bus pull out from the station going the other way. It was going quite fast then it hit us and the Magic Bus behind us.
"I was shaking and a girl behind me on the bottom deck was really panicking. People were thrown around. It was really scary but I'm ok."
Paramedics attended the scene and treated around 10 passengers, while crowds of shocked onlookers gathered to take pictures on Portland Street.
Portland Street and Picadilly bus station were shut for about two hours after the crash, and reopened around 11am.
A spokesperson for Stagecoach Manchester told Mancunian Matters: "Our first concern is for the safety of our passengers and drivers. We are working with the emergency services to ensure those involved in the incident are given every assistance.
"Safety is our absolute priority and a full investigation into the incident will take place to identify the cause of the accident. We are also working closely with the emergency services to clear the incident to minimise disruption to travel."
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