Two explosions have hit the Boston Marathon.
According to Boston police, two people are dead and 23 are injured.
A local TV station said the blasts occurred near the famous race's finish line.
"Witnesses said several victims lost limbs, and the area was being evacuated," WCVB reported.
AP quoted a Toronto runner who heard two explosions.
"There are people who are really, really bloody," Laura McLean said. "They were pulling them into the medical tent."
On Facebook, race organizers posted: "There were two bombs that exploded near the finish line in today's Boston Marathon. We are working with law enforcement to understand what exactly has happened."