This undated handout photo made available by the Kiel-based GEOMAR oceanographic research centre on March 23, 2026 shows a mine with open shell and TNT in the background on the seafloor of the Baltic Sea. Just a few kilometres from the beaches of northern Germany's Kiel Bay, huge quantities of World War II munitions are slowly disintegrating underwater near where summer crowds dive in from the beaches. This site, one of the most polluted in the Baltic Sea, is the starting point for the expedition of the scientific research vessel Alkor, belonging to the Kiel-based GEOMAR oceanographic research centre. The ship's crew of 11 sailors and a dozen scientists from Germany, Poland and Lithuania are spending three weeks aboard studying how these toxic weapons dumping grounds are contaminating the waters of the Baltic, one of the regions of the globe most affected by munitions and shipwrecks. (Photo by Handout / GEOMAR / AFP via Getty Images) / RESTRICTED TO EDITORIAL USE - MANDATORY CREDIT "AFP PHOTO / GEOMAR" - HANDOUT - NO MARKETING NO ADVERTISING CAMPAIGNS - DISTRIBUTED AS A SERVICE TO CLIENTS