Updated Wednesday, January 9, 2013 at 09:00 PM
An attorney for the Canadian travel company whose bus crashed and killed nine passengers in Oregon says the driver had more than seven hours of sleep the night prior to the accident.
Mark Scheer - attorney Mi Joo Tour & Travel - says black ice was a factor in the Dec. 30 crash near Pendleton, Ore. The crash left 38 people injured, including the driver.
Scheer's comments come a day after the U.S. Department of Transportation revoked the travel company's authority to provide passenger service in the United States after determining a driver was not properly rested when his bus crashed.
A federal investigation found that driver Haeng Kyu Hwang had been on duty for 92 hours in the eight-day stretch before the tragedy, exceeding the 70-hour federal limit.