An as-yet-unidentified container ship marked with CMA CGM on the side sailed right through a mass swim organized by San Francisco area swim club Odyssey Open Water Swimming from Alcatraz to St Francis Yacht Club on the east side of San Francisco

The final part of the Swimming For Alcatraz event involved more than 80 swimmers, who saw the container ship cross their course, coming very close to the swimmers.

The US Coast Guard was reported to be investigating the incident which was caught on video by TV station KRON. Fortunately there were no injuries.

Odyssey Open Water Swimming has been organizing events in the area for a decade, reporting on its website. There were 81 people signed up for the Saturday November 4th event, with participants being told to meet at 06:45. The swim was due to start one to two hours later and to be over by 10:45.

The swimming group reported to KRON that the course had been cleared by the US Coast Guard and they had a permit issued almost a year ago for Saturday’s swim.

Sailing through the last of the morning fog on San Francisco Bay, one of CMA CGM’s containerships – heading out of Oakland and towards the Pacific if the video was shot from San Francisco – can be seen moving through the bay with the swimmers and their support boats/escorts nearby.

Warren Wallace, a local athlete and swim coach who organized the group told KRON that “our support team, paddlers, and swimmers acted very quickly to react to the unexpected breach to the course”, adding with a degree of understatement that “large commercial vessels merging into our planned path is not a normal occurrence”.  He said that Odyssey was “anxiously awaiting information on why this occurred.”