The pilot of a Continental Airlines flight became ill after takeoff and was later pronounced dead after the plane made an emergency landing, a company spokeswoman said.

The 210 passengers on the flight, which departed from Houston, were never in danger and the co-pilot landed the plane safely Saturday, Continental spokeswoman Macky Osorio said.

The airline said only that the pilot suffered a "serious medical problem." Continental believes the pilot died of natural causes, Osorio said. The pilot's name was not released.

The flight, bound for Puerto Vallarta, Mexico, took off from Houston's George Bush Intercontinental Airport and was diverted to McAllen-Miller International Airport. The flight continued to Mexico with a new crew, Osorio said.