A central witness in the investigation into the disappearance of Madeleine McCann has life-threatening cancer, a court heard on Friday.

Helge Busching has intestinal cancer and is not expected to live long, a friend of his told the court during the trial of Christian Brueckner in Germany. Brueckner is the chief suspect in the McCann case but this trial is unrelated.

Mr Busching is the prosecution’s key witness in the current trial, in which Mr Brueckner is accused of five counts of sexual assault in Portugal between 2000 and 2017.

Mr Busching, 53, claims to have found home-made tapes in Mr Brueckner’s home in 2006 that showed him raping two women.

On Wednesday, he described the details of the tapes to the court, saying that Mr Brueckner wore a balaclava but took it off to reveal his face. The tapes no longer exist and the police have never seen them.

Mr Busching also told the court that Mr Brueckner hinted to him during a meeting in 2008 that he had been involved in the abduction of Madeleine, telling him “she didn’t even scream”.

On Friday, Michael Tatschl, another witness in the case, said Mr Busching has cancer, in comments reported by Sky News: “When we spoke... on the phone, we discussed general things including his cancer. It’s pretty bad. He got his diagnosis just a couple of months ago.”

Mr Tatschl told the court that he often stayed overnight at Mr Brueckner’s house in Praia da Luz, the town where Madeleine went missing in 2007.

Mr Tatschl described their relationship as “friends and partners in crime”. He said that he saw a whip, several pairs of handcuffs and a balaclava in Brueckner’s home.

In 2006, the two men were sentenced to eight months in jail in Portugal for stealing diesel from a lorry.

During their time in prison, Mr Brueckner told him that he had held a young woman captive for several days, Mr Tatschl said.

Prosecutors opened the investigation into Mr Brueckner on suspicion of murdering Madeleine back in 2020, but have yet to bring the case to court, perhaps suggesting they do not have enough evidence to charge him.

Mr Busching is set to appear in court again in June. The trial is scheduled to last until October.