Three people were killed Wednesday when a jeep sped out of control through a crowd of several hundred people at a US car auction in Massachusetts, officials said.
Nine other people were hospitalized -- including two with life-threatening injuries -- after the warehouse crash at Lynnway Auto Auction, a used car dealership in Billerica, just over 20 miles (35 kilometers) north of Boston.
"The preliminary information we have right now suggests that this is a tragic accident," Middlesex District Attorney Marian Ryan told reporters.
"At about 10:13 this morning police received a call of a vehicle that had gone out of control," she said.
Several hundred customers and staff had gathered for the weekly auction, where employees drive cars up and down lanes to be viewed for sale.
A Jeep Grand Cherokee "suddenly accelerated and traveled through the building at high speed," said Ryan. It struck members of the crowd before crashing into a cinder block wall at the far end of the warehouse.
"One male and two females have died as a result of their injuries," said Ryan. Nine other people were being treated at a hospital, including two with life-threatening injuries, she added.
The driver is a man in his 70s who works for the company. Reports suggested that he may have suffered a medical emergency, but Ryan said he was not hospitalized.
Massachusetts State Police said earlier there was "no evidence or information to suggest the incident was caused by an intentional or terrorist act."
"All evidence and information at this time suggests an accidental cause."