The CEO of Uber, Travis Kalanick, lost his mother, Bonnie Kalanick, to a boating accident, Friday, in Pine Flat Lake in Fresno County, California.

Bonnie, 71, was out boating with her husband, Donald Kalanick, when a rock hit their boat, causing it to sink and injuring both in the process, according to the preliminary reports revealed by the Fresno County sheriff's office, BBC reported. 

Emergency services were called on the scene and found the Kalanicks severely injured. While Bonnie Kalanick died at the scene, her husband was taken to a nearby hospital.

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Travis’ parents, who live in Northridge, Los Angeles, are longtime boaters and had been sailing down the local waters for years.

An autopsy is scheduled to be carried out, Sunday, after which, more details about the incident will be revealed.

Liane Hornsey, the chief human resources officer of Uber, called the incident an “unthinkable tragedy”. She wrote in an email to her staff that “everyone in the Uber family knows how incredibly close Travis is to his parents”.

Travis posted a photo with his parents on Twitter on May 6, when all of them went to the Kentucky Derby together.

Uber or Travis are yet to release an official statement regarding the matter. Many people took to social media to offer their thoughts and prayers on the terrible loss that Travis has suffered.

Travis’ loss could not have come at a more difficult time, as he and his company have been making headlines for all the wrong reasons lately.

Uber was forced to admit recently that it has “mistakenly” underpaid its drivers, working in New York, for almost two and half years by deducting 25 percent of their commission from the total fares charged before taking into account the taxes, while it was actually supposed to do that after the local taxes and fees have been calculated.

This violated a vital clause in the agreement, struck between the driver and the company at the time that they were hired. Uber has since vowed to pay back $900 to every driver who missed out on their rightful commissions due to the error on the company’s part.

"We made a mistake and we are committed to making it right by paying every driver every penny they are owed, plus interest, as quickly as possible," Rachel Holt, Uber's regional general manager in the U.S. and Canada, told the Wall Street Journal.

Also, earlier this year, Travis was caught on camera swearing at one of Uber’s drivers, an action that was condemned by many people all over the world, Evening Standard reported.

Later he apologized to his staff via email, saying that he was “ashamed” of his actions. “My job as your leader is to lead… and that starts with behaving in a way that makes us all proud. That is not what I did, and it cannot be explained away,” he added.