Sheryl Sandberg assured friends and family that she wasn’t on the flight, while Samsung’s David Eun was shaken up but safe.

Leading tech executives returning from South Korea, where Sheryl Sandberg was promoting her book "Lean In," were stunned as a plane on its way back from the event crash landed in San Francisco.

Sandberg, during her speech at Yonsei University in Seoul, South Korea, on Wednesday, July 3.

Via: Bloomberg / Getty Images

Samsung's David Eun tweeted the harrowing news of the plane crash and said he was hit with memories of September 11, 2001.