The bus, operated by Megabus and carrying about 70 passengers, left the road about 5:30 a.m. Saturday on Interstate 65 in Seymour, Indiana State Police Trooper Clifton Elston said.
Twenty-seven people from the bus were treated for minor injuries at Schneck Medical Center in Seymour, hospital spokeswoman Stephanie Furlow said. Jackson County Emergency Medical Services Supervisor Roger Wheeler told The Tribune of Seymour a pregnant woman with a cut to her head was taken to an Indianapolis hospital.
Wintry weather conditions, including snow flurries and wind, as well as speed may have contributed to the crash, state police said, noting several other accidents were reported in the area, about 60 miles southeast of Indianapolis. The investigation is continuing.
Hughes said Megabus was "assisting the authorities with their investigation" into the accident.
In October, a Megabus following the same route was involved in a crash on I-65 just south of Indianapolis, in which several people were injured.
Greenwood Fire Department Battalion Chief Chris Harrell told reporters at the scene in October that one person was taken to a hospital in critical condition, while four people had moderate injuries and 14 had minor injuries.
The bus carrying between 50 and 60 people crashed about 4:30 a.m. on Interstate 65 when its driver apparently swerved to avoid a minor crash that had occurred about 10 minutes earlier, state police Sgt. Shawn O'Keefe said.
"The driver apparently didn't see it because of the rain or something and swerved to avoid it," O'Keefe said. "The bus driver swerved and ended up turning the bus over on its side, and it went into the median."
In December 2013, the federal government put 52 bus companies out of business, ordering a total of 340 passenger vehicles off the road, as part of a effort to shut down unsafe motorcoach companies. As The Christian Science Monitor reported:
“Bus travel is increasingly popular because it is a convenient, inexpensive option for students, groups and families,"Transportation Secretary Anthony Foxx said in a statement. "But it must also be safe. Through Operation Quick Strike and our regular enforcement efforts, we’re shutting down companies that put passengers at risk and educating the public on safe motorcoach travel."
The motorcoach industry carries about 700 million passengers a year in the United States, roughly the same as domestic airlines do, and transports a wide variety of passengers, ranging from school bands to senior citizens.