Ed Gilligan, president of American Express
© @edgilligan/Twitter Ed Gilligan, president of American Express, died Friday.
The president of American Express died on board a plane bound for New York City on Friday.

According to the company, Ed Gilligan became seriously ill on a flight home from Tokyo and passed away. No other details about the incident were immediately released.

The 55-year-old, life-long company employee was returning from a business trip on a corporate jet.

In a letter to employees Chief Executive Officer Ken Chenault stated: "This is deeply painful and frankly unimaginable for all of us who had the great fortune to work with Ed, and benefit from his insights, leadership and enthusiasm. Our thoughts and prayers go out to his wife, Lisa, and their four children - Katie, Meaghan, Kevin and Shane. He was a proud husband and father, and his love for his family was evident in all that he did."

Gilligan started as an intern at the company 35 years ago. He became Vice Chairman in 2007 and President in 2013.

The company plans a memorial service for employees to share their memories of Gilligan. Details were still being worked out.

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