The ocean is filled with shipwrecks, but its vastness makes them extremely difficult to find, especially if you’re not exactly sure where to look. While amazing discoveries are possible, disappearances are too.

And vanishing is exactly what three Dutch warships from WWII recently did. The three ships were discovered in the Java Sea, a strip of ocean between the Indonesian Islands of Borneo and Sumatra.

Two of the ships have completely vanished from the site, while only a part of the third remains. In a statement published by The Guardian, the disappearance of the ships is confirmed.

“The wrecks of HNLMS De Ruyter and HNLMS Java have seemingly gone completely missing. A large piece is also missing of HNLMS Kortenaer,” said the Dutch defense ministry.

Sonar imaging has confirmed that divers are in the right place, exactly where the ships were discovered, but no ships are being found. The massive imprints are all they left behind.

The wrecks were originally discovered in 2002, and a visit was planned for next year to commemorate the 75th anniversary of the Battle of the Java Sea.

Now, it seems there’s some rearranging of plans to be done.

Other wrecks in the same area have been pillaged for small parts such as shell casings, but the size of the wrecked ships makes a theft unlikely.

The ocean is a source of life, mystery, and even beauty. In fact, the oldest known jewelry ever found was made of 100,000 year-old seashell beads.

Despite the fact that a theft is unlikely, the Java Sea is both shallow and easy to access, which means that this particular wreck may have been a target for scrap metal.