Tamara Lynette Green, 30, and her cousin, Gary Benjamin Green, 27, who was driving, died Sunday after a number of Green family members attended the game between the Hornets and the Detroit Pistons at the Palace of Auburn Hills, the Detroit Free Press reported.
There were no witnesses to the 12:40 a.m. accident on southbound Interstate 75, police said.
"They went off the roadway at a high rate of speed, went airborne and hit the tree with the roof of the car," Troy Police Lt. Robert Redmond said. "It wasn't the road conditions; the road was fine. It was the speed. Where there's the least amount of protection is the roof of the car."
Investigators said they believed alcohol may have been a factor in the accident but were waiting for test results for confirmation, Redmond said.
Willie Green, already in Indiana for a Hornets game against the Pacers Monday when he was informed of the accident, left to return to Detroit after the Hornets told him to take as much time as he needed to deal with the tragedy, the Free Press reported.