Chyna Thomas, sister of NBA basketball player Isaiah Thomas, died in a car crash Saturday morning near Federal Way.

The 22-year-old was driving southbound on Interstate 5, just north of South 288th Street, at 5 a.m. when a witness saw her Toyota Camry drift off the roadway and strike a jersey barrier. Her vehicle landed on the barrier, striking a pole.

According to Washington State Patrol, she was not wearing a seat belt.

Trooper Rick Johnson said investigators don’t believe she was impaired. That will be confirmed, however, after toxicology reports are complete. Johnson said witnesses reported no erratic driving, no speeding or prior lane change issues.