TACOMA, Washington (NEWS CENTER) --

Boston Celtics' star point guard Isaiah Thomas' sister was killed in a car crash in Tacoma, Wash. early Saturday morning according to Washington State Patrol.

Patrol reported that 22-year-old Chyna Thomas was found deceased at the scene after she went off the roadway and struck a jersey barrier, landing on it and hitting a pole. Police said Thomas was driving southbound on Interstate 5 near Federal Way around 5 a.m. Police said only one car was involved, and that Thomas was not wearing her seatbelt.

The Boston Celtics released a statement Saturday night:

"We are terribly saddened by the tragic loss of Chyna Thomas. The thoughts & prayers of the entire organization are with Isaiah & his family."

Isaiah Thomas, the Celtics star point guard, tweeted Thursday that he would remain off social media as the Celtics prepare for their first-round matchup against the Chicago Bulls on Sunday night.