Witnesses say the SUV shot down Rainier Avenue South at a high rate of speed just before 1:30 p.m.
"She was going at least 50 mph," said witness Kathy Whitcomb.
At some point the car jumped the curb at S. Ferdinand Street, bashing its way into the corner building. Before the car stopped moving, it pinned a mother, father and 10-year-old daughter against a wall as they ate in a restaurant next door. Three people in the salon were also hurt, including a 6- to 8-year-old boy. The 40-year-old driver was also injured and was trapped inside her car by falling debris.
Then flames broke out.
"And we saw the black smoke," Whitcomb said.
Witnesses say people rushed in to help, scrambling to free the victims who were trapped.
"Everyone was rushing toward the building, and trying to pull the chairs and wood and debris out of the way," said witness Karla Esquizel.
Seattle Fire spokesman Kyle Moore said the Good Samaritans included an off-duty firefighter.
"There were several spot fires underneath the SUV," Moore said. "He was able to grab extinguishers from nearby restaurants and was able to put out those spot fires."
Firefighters say four of the seven people hurt in the crash suffered burns from those flames, but none of the injuries are serious.
The next focus was on keeping the building standing. Moore said the crash may have compromised the building's structural integrity. Two cracks have formed in the walls and are still expanding, he said.
"We're worried about whether this building might collapse, so we're bringing in engineers from the city to determine the structural integrity of the building," Moore said.
Meanwhile, the hair salon owner says she's thankful no one was killed, but can't believe what's become of her business.
"Spent a lot of money in redoing it and look at it now, it's a tragedy, gosh," said Carol Cobb.
Police are still investigating what led up to the crash.