Neighbours heard a commotion in the flat the two men shared in Norwich shortly before emergency services were alerted in July 2007, jurors at Norwich were told.

But David Farmbrough, 52, of Market Place, Driffield, has denied murder. He told police his son died accidentally.

Prosecuting, Ian James, told the court: "The cause of the row between father and son will probably never be known."

In statements to police, David Farmbrough claimed noises heard by neighbours from the flat that night were caused by his son and himself dancing.

Previously, the prosecutor had said that Mr Farmbrough had said that Peter was alone in the kitchen when he received the terrible injury which was the product of an accident or, for some reason, Peter had used the knife to end his own life.

Mr James claimed that Mr Farmbrough's explanations were 'not plausible' and not consistent with the police facts.

"We claim he is telling lies and is guilty of murdering his son, " said Mr James.

"We say they both argued and did so fiercely. Mr Farmbrough had banished Peter from the flat and there was some physical confrontation between them and at some stage Mr Farmbrough had used the knife to stab his son.

Only two people know and one of them is dead, " said Mr James.

Peter Farmbrough's sister Hollianne gave evidence via a video link.

She said she had a phone call from Peter about a month before he died.

He asked her to take a note of what he was saying. He said he was frightened his father would come to her and do what he was doing to him.
"He didn't go into any detail about what he meant," she said.

She added she had torn up what she had written so that her sister would not find it and show it to their mother.

She said there were five children in the family. She was born in Scotland in November 1991. The family had broken up and the girls had stayed with their mother whilst Peter and another brother Ashley had come to East Anglia with their father.

Her father and the two boys had come to Scotland in July 06 and then her mother apparently didn't want them to come again.

An aunt, Susan Vosper who lives in Great Yarmouth said when Peter was 16 he had come to her house and had red marks on his neck and scratches on his face. She claimed Peter had told her his father had done that when he had refused to go door to door to collect money for charity.
She claimed Peter told her the year before this, his father had kept the money.

The trial continues.