The NATO frigate was supposed to be difficult to detect. Located thanks to a postcard with a transmitter

Ashley Davis26/04/2026

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The accident was reported by the Dutch regional publisher Omroep Gelderland. Journalist Just Vervaart reported that he was able to track it down HNLMS Evertsen, Dutch air defense frigateare part of a NATO strike group in which its mission is to protect the Charles de Gaulle aircraft carrier from missile threats.

Locating Evertsen turned out to be extremely easy, and was made possible thanks to Bluetooth locator on board the frigate. Such a locator, a generic equivalent of Air Tag, is possible buy online for a few euros and it is usually used, for example, to find keys. However, it turns out that such a gadget is perfect for tracking the location of a frigate that is supposedly difficult to detect.

sample locator on Aliexpress

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AliExpress

HNLMS Evertsen – air defense frigate

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Dutch Ministry of Defense

How did the tracker end up on board the Evertsen?

The postcard with the transmitter was on board via Military Postal Organizationi.e. the post office of the Ministry of Defense, which makes it possible sending letters and parcels to soldiers and sailors in the Dutch armed forces. The Ministry of Defense provides appropriate online instructions for this purpose.

Of course, the ministry checks whether any prohibited or dangerous items are sent by post. Posted videos and shipping guidelines show packages passing through an X-ray scanner. However, they also reveal that unlike parcels, letters are no longer screened. Therefore, the transmitter packed in an envelope was not detected and reached the ship.

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The fact that the transmitter was sent by post means that potential spies wouldn't even have to approach the shipto place the transmitter on it.

Route

The entire locator route could be followed online. The envelope leaves the sorting center and, after a stopover at the Den Helder naval base, arrives at Eindhoven airport. From there he continues his journey to Crete, to the port of Heraklion. The webcam footage shows that The Evertsen is moored there at the quay.

On the morning of March 27, a webcam shows Evertsen heading out to sea. The ship soon disappears from the camera's view, but thanks to the transmitter its location can still be tracked from thousands of kilometers away. You can see it's a frigate it first flows west along the coast of Creteand then sets course to the east. Only 24 hours laterwhen Evertsen is already there near Cyprusthe locator is turned off and no longer works.

HNLMS Evertsen – Bluetooth locator revealed the location of a Dutch warship

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Omroep Gelderland

It was not possible to determine whether the Dutch frigate was already in the vicinity of the French aircraft carrier Charles de Gaulle, which was operating in the region at that time.

The Ministry of Defense is taking action

According to Dutch Ministry of Defense officials interviewed by Vervaart for his article, the transmitter was discovered and ultimately disabled while sorting mail on the ship after the frigate had sailed out of port. Although the ship could be tracked at sea, the ministry said it did not pose an operational threat.

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The ministry spokesman also said that some changes had been made after the incident. You can no longer send letters and greeting cards containing batteriesand the ministry will further review guidelines for sending and checking military mail.

Information on how to send mail to a warship remains available online because the Ministry of Defense believes thatit is important that soldiers can maintain contact with their families and loved ones.

However, caution must be exercised between enabling communication and protecting against the accidental disclosure of key secrets. Cutting off soldiers and sailors from regular mail during missions will lead to a drop in moralebut technology has changed and something that was once as harmless as sending mail to soldiers must be considered in a new light.

This is not the first such case

However, it was social media that turned out to be a real disaster for the military in terms of operational security. Even the most innocuous post can accidentally contain information that is extremely valuable to an adversary.

Among the more interesting cases: just over a month ago, the LeMonde.fr portal reported that the location of the Charles de Gaulle aircraft carrier itself was revealed by one of the sailors stationed on it, who published his time and route in the Strava application. This revealed the location of the aircraft carrier in the Mediterranean Sea, as intelligence from publicly available sources could potentially identify the officer in question and his position in the French Navy.