Danish police said today they had found nobody in the wreck of a submarine owned by an inventor charged with the manslaughter of a woman who had been on board - but added the vessel seemed to have been deliberately sunk.

Police have said that Swedish journalist Kim Wall, 30, is missing after taking a ride on Peter Madsen's homemade 17-metre sub, which sank on Friday morning. Mr Madsen was rescued by the navy.

Mr Madsen, 46, has been ordered to be held in custody for 24 days, accused of Ms Wall's manslaughter.

The vessel was recovered yesterday from Koge Bay, south of Copenhagen, where it had been lying at a depth of seven metres, and taken into harbour. Police searched it late yesterday and early today.

Kim Wall Peter Madsen

"There are no persons in the submarine, dead or alive," Jens Moller, head of Copenhagen Police's homicide unit, said at a news conference.

He said it appeared to have been deliberately scuttled, and was still being treated as a possible crime scene.

Mr Madsen, an entrepreneur, artist, submarine builder and aerospace engineer, went before a judge yesterday for preliminary questioning. His defence lawyer, Betina Hald Engmark, said he denied the charges.

Police said on Friday the inventor had told them he dropped Ms Wall off from his submarine in Copenhagen on Thursday night. Today, they said they had since been given another explanation by Mr Madsen, but declined to elaborate.

Police in Sweden said they had tried without success to contact Ms Wall by phone and that her family had not heard from her.

The submarine, UC3 Nautilus, is one of three constructed by Mr Madsen. It can carry eight people.