B.C.'s Queen of Nanaimo ferry was damaged and at least five people were injured when the ship collided with a dock while coming into harbour early Tuesday morning.

The ferry, which runs between Tsawwassen and the Gulf Islands, collided with the dock in Village Bay, Mayne Island, at about 7:30 a.m. local time.

There were about 200 people on board. They were warned to brace for impact about 30 seconds before the ferry struck the dock.

Six people were treated for non-life threatening injuries stemming from the accident, according to a release from Sgt. Rob Vermeulen of the RCMP.

Most of the injured reportedly suffered broken bones. An elderly woman had to be airlifted to hospital in Vancouver after the collision sent her flying into a pole in the ship's cafeteria.

A ferry employee was also injured. She had been standing on the dock when the collision took place.

Police, Coast Guard and members of the Mayne Island Fire Department responded to the incident.

"Once the ramp is inspected and cleared, the RCMP will assist with identifying passengers as they disembark, and a search of the vessel," said an RCMP release.

There is no word yet on what caused the accident, known as a "hard landing."

Mike Corrigan, chief operating officer of BC Ferries, which operates The Queen of Nanaimo, said the vessel was travelling too quickly as it prepared to dock.

"There's a number of potential reasons for that," he said. "We don't know what they are right now -- we'd be speculating to guess."

BC Ferries will launch a "full investigation" to determine the cause, Corrigan said.

"It's an extremely rare event," he added. "We have 185,000 sailings a year."

The ferry was damaged in the collision. It's not clear when it will resume service.

With files from CTV British Columbia's Jon Woodward