Danish police said they were preparing to search a sunken submarine owned by Danish inventor Peter Madsen who has been charged with the inadvertent manslaughter of a journalist.

Police said that Mr Madsen, 46, was being held in custody, accused of killing Swedish woman Kim Wall, 30, who they said had been on his submarine before it sank yesterday.

Mr Madsen was rescued in a navy operation and taken ashore after his homemade 17-metre submarine went down.

The vessel was recovered today in Koge Bay, south of Copenhagen, at a depth of seven metres, and taken into harbour.

It will be partly drained of water and searched by the police.

Peter Madsen

Mr Madsen, an entrepreneur known as an artist, submarine builder and aerospace engineer, went before a judge today behind closed doors for preliminary questioning.

His defence lawyer, Betina Hald Engmark, said he denied the charges.

The police said yesterday the inventor had said he had dropped Ms Wall off in Copenhagen on Thursday night.

The police in Sweden said they had tried without success to contact her 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.