Danish police have charged Peter Madsen, 46, with manslaughter following the disappearance of a female Swedish journalist who boarded his submarine, the Nautilus, at Refshaleøen in Copenhagen on Thursday evening.
Madsen, whose submarine sunk near Køge on Friday, denies the charges. He claims he dropped the woman off at Refshaleøen three hours later.
However, when she failed to return home later that day, her worried boyfriend contacted the authorities, which led to a full-scale search for the submarine in the early hours.
No search yet
Copenhagen Police confirmed the charges on Friday evening, but its divers have been unable to enter the submarine thus far.
It is believed a search will be carried out once the vessel has been towed to port later today.
Madsen, who is well-known in Denmark as a co-founder of amateur rocket group Copenhagen Suborbitals, managed to escape the sinking vessel.
According to the BBC, the woman has been identified by friends as Kim Wall, a freelance journalist based in Beijing who travels extensively.
A look at her Facebook page reveals she has written stories all over the world for the likes of the New York Times and the Guardian.
Copenhagen Police have appealed for witnesses who might have been at Refshaleøen at around 19:00 and 22:30 – the times Madsen claims his submarine left and returned.