The seaplane crash that killed six people near Sydney, Australia on New Year's Eve might have been caused by a passenger knocking the pilot unconscious by accident, according to a local news report.

Gareth Morgan, a 44-year-old from British Columbia, was piloting the Sydney Seaplanes aircraft when it listed hard right and crashed into the Hawkesbury River over 10 months ago, killing everyone on board.

The cause has never been confirmed, but the company recently told The Australian newspaper that Morgan was potentially struck in the head by a passenger trying to snap a picture.

"The investigation has shown that safety is good and it's actually believed to not be pilot error," Jerry Schwartz, a partner at Sydney Seaplanes, told the paper.

"The current belief is the passenger at the front actually knocked out the pilot."

The Australian Transport Safety Bureau previously confirmed the crash was not caused by a bird strike or bad fuel, but could not provide a concrete cause.

The crash puzzled Morgan's coworkers, who noted that he was an experienced pilot with more than 10,000 hours of experience, 9,000 of which were spent in seaplanes.