MONTPELIER, Vt. – A tour bus carrying University of Massachusetts students and others on a weekend ski trip to Quebec crashed Friday on a Vermont highway, injuring 17 people.

The bus, one of three traveling in a caravan, veered off Interstate 91 in Putney and went down an embankment, coming to rest on its side. Twenty-eight people on the bus were unhurt.

The bus driver was taken by helicopter to Dartmouth-Hitchcock Medical Center in Lebanon, N.H., and was listed in stable condition.

The group was on a private ski tour that was not affiliated with the school, UMass spokesman Patrick Callahan said.

Seven passengers were taken to Brattleboro Memorial Hospital with cuts and bruises, and they were treated and released, spokeswoman Barbara Gentry said. An eighth had a neck injury, but he, too, was released. Eight passengers with minor injuries were treated and released from Springfield Hospital.

It’s unclear how the crash occurred, said Stephanie Dasaro, a spokeswoman for the Vermont State Police. A crash reconstruction team was on the scene investigating Friday night, she said.