TOFINO, British Columbia (AP) _ A whale-watching boat capsized in rough seas off Vancouver Island, killing two of its four passengers.

A third passenger was in critical condition today in a hospital in Tofino, British Columbia, said Air Force Capt. Jamie Davidson of the rescue coordination center in Victoria.

Rescuers found the two dead and one injured passenger floating in the frigid water Sunday. The fourth passenger was found in shock on the boat, which apparently righted itself after capsizing.

Rescue officials were notified Sunday by the tour operator, Jamie's Whaling Station Dock, that one of its boats had failed to return from a scheduled tour.

An air search crew spotted the four about six miles from Tofino. They were wearing special foam suits that kept them afloat, acting as life preservers and wet suits.

The names of the victims were not released.

Police said the group was on its way back to Tofino when high waves swamped the vessel.

Whale watching is a popular tourist attraction in the area.

Anne Sheridan, who operates Seaker Adventure Tours in Victoria, said tour operators warn passengers about the risks involved and require them to sign waiver forms and wear the full-length survival suits.

``You can usually have four or five hours in the water before you go hypothermic,'' she said.

It was unclear how long the group had been in the water before rescuers arrived.