A coast guard officer in the United States was forced to open fire on a shark after it was spotted heading for dozens of crew members enjoying a swim.
The crew had not been off the ship for weeks and decided to enjoy some time in the sea to "break up the monotony" of being on board.
But a shark was soon spotted heading towards the group, and an officer opened fire on the creature to scare it away.
The crew confirmed that the shark was not injured and the "goal was to keep it away from shipmates".
The story was shared on the US Coast Guard Cutter Kimball Facebook page.
The post said: "After completing our operations for the day, there were no vessels around for miles, the weather was perfect, and we were a zillion miles from land.
"We had not been off the ship for weeks, were at that point where every day feels like 'Groundhog Day', and were looking for something to break up the monotony."
Explaining how the drama unfolded, it said: "As if right out of a Hollywood movie, a six to eight foot shark (no exaggeration) surfaced at the Rescue Door and was swimming towards 30 to 40 people in the water about 30 feet away.
"Everyone on the Flight Deck had a bird's eye view. A review of video shot by a crew member reveals it was likely a Long-Fin Mako or Pelagic Thresher Shark - not something to mess with!"
A "well-aimed burst" was fired at the shark to protect the crew, who were swimming just metres away, the post said.
"It turned away for a few seconds then turned back. We kept directing people out of the water while keeping a clear line of sight on the shark," it said.
"The shark would wave off with each burst but kept coming back towards our shipmates."
The crew now had to work together to get everyone out of the water to safety.
The post said: "It wasn't the panic of the July 4 scene from Jaws, but once everyone realised what was happening, they moved with a purpose!
"Everyone stayed focused and worked the problem. The small boat quickly looked like a vessel overloaded with SAR survivors. Others threw heaving lines to shipmates in the water and helped them aboard via the stern notch."
Only one officer suffered an injury as he clambered aboard the boat, which "wasn't even worth a band aid".
"We have hundreds of years at sea between all of us and no one has seen or heard of a shark actually showing up during a swim call," the post said.
"This goes to show why we prepare for any and everything. We just didn’t think it would be a swim call shark attack."
For those concerned about the shark's welfare, an update shared on the Facebook page said: "For those asking about the shark, we don't think the shark was injured. Our goal was to keep it away from shipmates, not harm it if possible.
"It was most likely curious and not looking for a meal. We picked our location to try and avoid such an encounter but it is their ocean after all.
"It later joined a few smaller buddies that showed up and they swam off together."
