This article was written by Alex Hollings and originally published on Sandboxx.

A member of the “shark watch” on a Coast Guard cutter had to open fire on a shark this week to dissuade it from continuing to approach his crewmates.

When you’re out on the open ocean, even recreational activities require proper planning and safety precautions, as the crew of the Coast Guard Cutter Kimball demonstrated in dramatic photos released earlier this week.

A carefully planned swim call, or a period of recreational swimming organized by the ship’s crew, started like any other: Rescue swimmers were standing by and an armed “shark watch” was standing guard from an elevated position, keeping his eyes trained on the surface of the water for any signs of danger.

The Coast Guard maintains a “shark watch” or a “polar bear watch” any time crew members are in the water and there’s potential danger posed by indigenous wildlife. This time, it was Maritime Enforcement Specialist 1st Class Samuel Cintron who was tasked with keeping a lookout for any aspiring “Jaws” star as other members of the crew got a chance to kick back and enjoy the warm Pacific water.

It wasn’t long before Cintron and others spotted the grey silhouette of what appeared to be a longfin mako or pelagic thresher shark approaching the swimming crew. Cintron stood ready, and as the shark closed to within 30 feet or so of the swimmers, Cintron was ordered by his chief to open fire. The gunfire likely came as a real shock to the swimmers, many of whom were not aware of the approaching shark until the shots rang out.

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Cintron fired a “well-aimed burst right at/on top of the shark to protect shipmates just feet away,” according to a post on the Coast Guard’s Facebook page. At first, it seemed to do the trick. Yet the shark once again turned and approached the swimming crew, who were now working to evacuate the water in a calm and organized manner. As the shark once again closed to within 30 or so feet, Cintron fired another burst.

“ME1 fired bursts as needed to keep the shark from his shipmates with amazing accuracy. The shark would wave off with each burst but kept coming back toward our shipmates,” according to the post.

Maritime Enforcement Specialist 1st Class Samuel Cintron on Shark Watch (Coast Guard).

It’s important to note that bullets lose a significant amount of energy when they impact water. In fact, it’s common for bullets to come apart and tumble harmlessly in just a few inches of water. There was no blood in the water near the shark, and according to Coast Guard public affairs, there were no indications that the predator was injured in the incident.

The close encounter with the shark ultimately proved harmless. The entire crew returned safely back on board. There was only one reported injury: a scrape, ironically enough, right in the middle of a tattoo of shark jaws on one crew member’s leg.

This engagement is incredibly rare. According to Military.com’s Patricia Kime, the last reported shark sighting during a Coast Guard or Navy swim call was in 2009, and no shots were fired.

“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. This goes to show why we prepare for any [sic] and everything,” ship officials wrote.