More than 20 people were taken to medical facilities following a trolley collision in Boston on Friday, authorities said.
No one was being treated for non-life-threatening injuries, the Boston Fire Department tweeted.
The department said 22 people were injured, and Boston Emergency Medical Services put the number at 23.
Two Green Line trains colled near Boston University early Friday evening, The Massachusetts Bay Transportation Authority said.
Aerial footage of the scene from NBC Boston showed at least one train with a mangled front end and a swarm of first responders nearby.
Trolley service in the area was suspended, and shuttle buses were being used instead of trains.
The cause of the collision was under investigation.