Harbor patrol rescued seven people around 3 a.m. after the accident, the Boston Fire Department said in a tweet earlier.
Authorities believe the victim is a woman, the Boston Police Department said in a release.
Five people were taken to a hospital by emergency medical services, according to the fire department tweet. The ages and conditions of the patients were not disclosed.
Police are “actively reviewing the facts and circumstances surrounding this incident,” according to the press release. It is currently a death investigation.
Anyone with information regarding the investigation is encouraged to call the Boston Police Homicide Detectives at 617-343-4470.
source: cnn.com