Emergency services were on the scene, with three fire and rescue appliances including a specialist resource team and the Scottish Ambulance Service.
Reports were raised at 6.10pm on Saturday to the 4A First Bus crash on Cook Street near the city’s O2 Academy.
Police have confirmed Cook Street is closed at Centre Street.
Commerce Street is also closed and Salkeld Street is closed to the scene on Cook Street.
One person has been confirmed by First Bus as taken to hospital with “several other injuries” reported.
Ten people were taken to hospital when a bus hit the same bridge in May 2023.
A spokesperson for First Bus said: “I can confirm that one of our 4A service buses in Glasgow was involved in a bridge strike incident on December 14 around 6pm in which a double decker bus hit a railway bridge on Cook Street.
“We’re aware of numerous injuries, with one person being taken to hospital in an ambulance.“We have launched an immediate investigation and are also assisting Police Scotland with their enquiries.
“Our thoughts are with everyone affected by this incident.”
A Police Scotland statement read: “A number of roads in Glasgow are closed following a report of a bus crashing into a bridge on Cook Street around 5.55pm on Saturday, December 14.
“Cook Street is closed at Centre Street, Commerce Street is closed until Wallace Street and Salkeld Street is closed to Cook street.
“Emergency services are in attendance and drivers are asked to avoid the area.”
A passenger who was third from the front on the bus, told the BBC that the driver had taken a wrong turn and crashed “straight into the bridge”.
They said: “I was fine, the lady in front of me might have been concussed. The bridge itself wasn’t high enough to hit anyone’s heads but parts of the bus exterior have swung down.
“The man in the front seat was in a really, really bad state. He’s got a lot of blood and a massive gash on his head.”
The extent of injuries are not yet clear.
ScotRail services have been impacted by the crash in Glasgow
Train services between Glasgow Central and Ardrossan Harbour, Ayr, Largs, Gourock, Wemyss Bay and Paisley Canal have all be affected.
ScotRail says that all services will be “cancelled, delayed or revised”.
Ticket acceptance has been arranged with Stagecoach on the following services:
- Glasgow – Dalry on bus number X36
- Ayr- Stranraer on bus number 58/60
- Glasgow – Ayr on bus number X77
- Irvine- Ayr on bus number 14
- Irvine- Glengarnock on bus number 25
- Ayr- Largs on bus number 585
- Ardrossan- Saltcoats – Sevenston on bus number 12
- Saltcoats- Stevenston on bus number 18
