A 73-year-old woman aboard a British Airways flight this week who was thought to be asleep was actually dead, reportedly after suffering a heart attack mid-air.

Fellow passengers on the Thursday flight from London to Nice realized something was amiss when they landed and the woman remained completely still as others went about collecting their carryon luggage to disembark.

Others on the flight grew even more concerned when they were unable to rouse the elderly woman.

Frightened passengers alerted the flight crew, who called emergency services. Paramedics attempted to revive her, but were unable to, French news outlet The Connexion reported.

The woman was declared dead at 10 p.m.

She is suspected to have died from a heart attack, the French publication said.

British Airways confirmed to the Daily Mail that “sadly a customer passed away on a flight from London Heathrow to Nice.”

In June, a British man died on a flight from London to New York after suffering an asthma attack and dropping his inhaler.

Shimoin Brauer, 25, of London, fell unconscious when he panicked and his inhaler slipped from his fingers about 45 minutes before his flight was scheduled to land in the Big Apple.

The crew attempted to give him oxygen and perform CPR, but was unable to revive him.