“Police reported at least 23 were injured, but hospitals reported receiving more patients.
Massachusetts General Hospital was treating 19 victims, spokeswoman Susan McGreevey said. Tufts New England Medical Center had nine patients “and we’re expecting more,” said spokeswoman Julie Jette.
Organizers immediately stopped the race and locked down the marathon headquarters.
The elite women runners started the race at 9:30 a.m. and the elite men followed about 30 minutes later. About 27,000 runners were in the field for the Patriots Day race.
Smoke hung over the neighborhood as police cleared the thousands of spectators who had jammed the route.