Dale McMichael, vice-president of Executive Coach Inc., said the company based in Lancaster, Pa., was working closely with police to determine what happened.
"Safety has always been and continues to be our top priority," McMichael said in a statement. "While we cannot change what happened, we pledge our assistance to the family of the victim and survivors in the days and weeks ahead."
The RCMP said 10 people were injured when a bus carrying 20 passengers along the road in Cape Breton hit the ditch Sunday afternoon and landed on its side about three kilometres south of Neil's Harbour.
Greg Organ, chief of the Neil's Harbour-New Haven Volunteer Fire Department, said four people were airlifted to hospitals across Cape Breton. Police said at least three passengers suffered serious injuries and two were taken to Halifax to be treated.
Organ said the crash happened on a section of the highway that is accessible to firefighters.
"There are many, many places where if the bus went off the road it would be a recovery," he said, describing the numerous steep slopes along the scenic highland highway.
Cpl. Scott MacRae said passengers on the bus ranged in age from 40 to 80 years old. The woman who died was 70, said police.
All the tourists on the bus are believed to be from the United States.
The Cabot Trail, a route popular with tourists, was closed to public access Sunday afternoon while police, fire and medical crews responded to the crash. The bus was removed and the trail was reopened to traffic later that evening.
The cause of the crash is still under investigation. Police said the findings of a motor vehicle inspection of the bus were under review.
Note to readers: This is a corrected story. A previous version said the Jaws of Life were used by firefighters.