A video posted on social media has shown a bus in Birmingham come under attack from fireworks.
Police said they were investigating and reviewing footage. It is unclear when the incident happened but it has been widely shared over the weekend.
The West Midlands force said there had been a number of fireworks-related incidents in the city centre since Friday night, with 10 people aged between 13 and 23 arrested.
Seven have since been bailed with conditions not to enter the city centre. Inquiries are continuing.
The force said fireworks had been thrown near New Street, with others launched at buildings and police officers in the early hours of Saturday.
No one was injured in the incidents according to police who added they would not tolerate “such appalling actions”.
They said a visible police presence would remain around the city centre and that a dispersal order was in place.
