MIAMI -

A passenger on a flight from Puerto Rico was pronounced dead shortly after arriving in Miami on Tuesday.

Miami-Dade police spokesman Alvaro Zabaleta said the 77-year-old woman on American Airlines flight 1254 from San Juan was pronounced dead at 10:12 a.m. after the plane landed at Miami International Airport.

Police and passengers told Local 10 the woman was sitting in the back of the plane with a man passengers believed to be her son-in-law.

About an hour into the flight, the pilot notified passengers of a medical emergency onboard.

Several passengers witnessed flight attendants and paramedics tend to the woman, but they were not able to save her.

Homicide detectives were at the airport investigating, but foul play is not suspected.

The woman has not been identified as police work to notify next of kin.