LONDON — A man who died after going into convulsions while flying from Colombia to Japan was found to have swallowed 246 tiny packages of cocaine, officials said.

The man, a 42-year-old Japanese citizen who had begun his journey in Bogotá, became ill on an Aeromexico flight from Mexico City to Tokyo, which then made an emergency landing very early Friday at Hermosillo airport in the Mexican state of Sonora, according to a statement from the state prosecutor’s office there on Monday. He died before medical help could reach him, the prosecutor’s office said.

An autopsy found that he had 246 plastic parcels of less than an inch long in his stomach and bowels, the statement said. It determined that his death had been caused by a surge in blood pressure, the result of a drug overdose, probably after one of the parcels ruptured. The man’s name was given in the statement only as Udo N.

The grim discovery was a reminder of the global demand for recreational drugs, and of the extreme methods traffickers adopt to satisfy it. Recent reports on the United States’ southern border have detailed smuggling by methods as mundane as mules with backpacks, and as elaborate as catapults and compressed-air guns.