American Express company President Ed Gilligan croaks on a flight - Dead at 55

American Express said company President Ed Gilligan died suddenly Friday after falling ill while flying on a corporate plane to New York.

Gilligan, 55, was coming back from a business trip. The plane made an emergency landing in the U.S., an American Express spokeswoman said. She declined to say where Gilligan had been.

"This is deeply painful and frankly unimaginable for all of us who had the great fortune to work with Ed," said American Express CEO Ken Chenault, in a letter to employees Friday.

Gilligan began working at the New York credit card issuer and global payments company 35 years ago as an intern. He was named president of the company in 2013 and reported to Chenault.

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