There's so much fodder for conspiracy theories, in particular the Swedish government response to it. It happened during an interim period in Swedish politics, and both the current and the future prime ministers said that they would recover the bodies and the ship at any expense, but then turned around and wanted to pour concrete on top of it with all the bodies still inside. Then in 2004 it was revealed that Estonia had been used to transport secret military equipment twice, as recently as one week before sinking. Then there's all the scandals surrounding the official investigation and report. I'm not sold on any of the alternative theories, this hole could have been caused when the ship sank and hit the bottom, but the arrogance of Swedish officials in this case has been, and continues to be, infuriating.