A jaw-dropping set of photos are going viral on social media showing that volcanic activity is lifting sunken World War II vessels . It has all of the makings of a good and spooky Halloween tale, but the ships have actually been sitting there, visible on the coast for a while. Here’s what’s going on.

In August, an underwater volcano called Fukutoku-Okanoba in the Ogasawara Islands located some 800 miles south of Tokyo, Japan erupted. Fukutoku-Okanoba’s eruption caused a small islet (small island) consisting of pumice and volcanic ash to rise above the waves. A day after, the nearby Nishinoshima volcano erupted for the first time in a year. Japanese publication Asahi Shimbun an aircraft with reporters and experts to see what’s going on in the region and spotted the ghostly-looking ships sitting on the coast of Iwo To (Iwo Jima) in the process:

Dilapidated hulls dot the black sands on the western coast of the island now known in Japan as Iō Tō. The island, whose former Iwo Jima name translates to Sulphur Island, was stormed by U.S. Marines on February 19, 1945, the National WWII Museum. The battle lasted 36 days, with 70,000 Marines and 18,000 Japanese soldiers taking part. Nearly 7,000 Marines were killed and 20,000 wounded in one of the bloodiest battles the Marines have ever taken part in.

The ships , with some believing the ships to be artifacts from the battle; others calling them sunken battleships of the Imperial Japanese Navy. But the United States Air Force in Kadena, Japan offers a different explanation.

According Kadena Air Base, the ships littering the coast are believed to have been scuttled in an effort to build a pier after WWII.

History site Traces Of War , describing the 24 sunken ships as being used in an unsuccessful attempt at creating a breakwater to help facilitate getting supplies into the island.

You’re probably wondering how the ships appear relatively intact considering they’ve been battered by the sea for decades. As Kadena Air Base , those ships are made of concrete. Steel was in short supply due to its use in the war effort. As a result, some governments experimented with building ships mostly out of concrete. Here’s what a tanker made of concrete built for WWI looked like:

But these ships didn’t stick around for too long and as the Warfare History Network , a number of them were scuttled for use as breakwaters throughout WWII, including a bunch off of Omaha Beach. Some concrete ships sank after shattering from hitting obstacles or grounding.

These ships are said to be transport ships have actually been visible to a lesser degree for years. This is what the beach looked like in 2005:

However, as Japanese news outlet ANNnews , volcanic activity is causing the island to lift up, revealing more of the abandoned husks. Now, some of them appear to be out of the ocean entirely.

As UK publication the Telegraph , there are no civilians on the island and unexploded munitions are scattered throughout. At this time, those ships are going to remain where they are.