The aircraft landed safely in the East Coast Canadian province yesterday, where it was met by paramedics.
American Airlines spokesman Ross Feinstein says three flight attendants and four passengers were transported to hospital for further evaluation.
The seat belt light was on when the Boeing 767 carrying 192 passengers and 11 crew members encountered turbulence. At least four ambulances and a fire truck were seen on the tarmac in St. John's, Newfoundland. An hour after the plane landed, one ambulance remained.