The president of the operator of a tour boat that went missing off Hokkaido with 26 people aboard last weekend had repeatedly forced captains to depart despite high waves, sources with knowledge of the company's business said Thursday.

While the exact cause of the fatal accident remains unclear, the bodies of three males with life vests on were found the same day in waters off the east side of the Shiretoko Peninsula, roughly opposite where the 19-ton Kazu I issued its first rescue call on Saturday, according to the Japan Coast Guard.

Besides the three, 11 fatalities have already been confirmed. The sources said the operator, Shiretoko Yuransen, based in the town of Shari, has been known for frequently going ahead with sightseeing tours despite the chance of bad weather.