(SEATTLE) -- The sister of Boston Celtics star Isaiah Thomas was killed in a one-car accident on Saturday, according to Washington State police.
Police said Chyna Thomas, 22, died at the scene after her vehicle went off Interstate 5 in Federal Way, striking and landing on a barrier and hitting a pole.
A source told ESPN the NBA star found out about his sister's death after participating in team practice Saturday afternoon.
In a statement Saturday, the Celtics said, "We are terribly saddened by the tragic loss of Chyna Thomas. The thoughts & prayers of the entire organization are with Isaiah & his family."
We are terribly saddened by the tragic loss of Chyna Thomas. The thoughts & prayers of the entire organization are with Isaiah & his family.— Boston Celtics (@celtics) April 16, 2017
The NBA also extended condolences to Thomas and the Celtics in a statement.
"The NBA family mourns the tragic passing of Chyna Thomas and we send our deepest condolences to Isaiah, his family and the Celtics organization during this difficult time," NBA commissioner Adam Silver said.
NBA Commissioner Adam Silver released the following statement regarding the passing of Chyna Thomas, sister of Isaiah Thomas of the Celtics. pic.twitter.com/iPOFte2jzM— NBA (@NBA) April 16, 2017
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