The BBC reports that five people died in New Zealand after a birdwatching boat capsized, possibly after colliding with a whale. Eleven people, mostly from the birdwatching group, were onboard when the boat capsized on Saturday in Goose Bay near the town of Kaikōura.

Police declined to speculate on what had caused the accident, merely confirming the collision. But Craig Mackle, the mayor of Kaikōura, told reporters he believed the boat had hit a surfacing whale.

Mr. Mackle said conditions in the bay at the time were “perfect” and that officials assumed the whale had surfaced beneath the vessel, causing it to overturn. Locals said that both sperm whales and humpbacks are in the area.

If the boat had hit debris – for example a log – it would have left a large hole in the 8.5-meter (28-foot) boat, he added, which wasn’t apparent.

Survivors of the incident – including the boat’s captain – had all been taken to hospital and later released. One survivor sustained minor injuries.

Kaikōura is popular with fans of marine life and a number of local business offer boat trips and helicopter rides to see whales and dolphins.

Mr. Mackle told the Associated Press that such accidents are unheard of in the region, but the number of whales in the area in recent days had caused him to worry about a collision.

Thanks to Alaric Bond for contributing to this post.