A mother found her son in a blood-soaked armchair, a trial has heard.
Darren Steel, 39, is standing trial at Swansea Crown Court, accused of the murder of his older brother Martin.
Steel, from Morriston in Swansea, denies murder and an alternative charge of manslaughter.
Prosecuting, Caroline Rees KC described him as being “jealous” of his brother and added that the brothers had a “love-hate” relationship.
Ms Rees told the jury the defendant was “in an angry state” and “consumed by rage” when he “brutally attacked his brother”.
“The defendant did nothing to try to save him. Did nothing to call an ambulance,” she added.
The jury heard Martin Steel had been left in a blood-soaked armchair until he was found by his mother, Diane Steel, on 20 May last year.
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She arrived at the house after neighbours raised concerns, having found Martin Steel’s dog covered in a “reddish brown” substance and after getting no response at the address.
‘Most horrific scene’
When Mrs Steel arrived, she found her son Martin with a swollen face and blood splattered around the room.
His mother said Darren Steel then came into the room, laughing and claiming he was “still pissed from the night before”.
“The defendant made his escape from the scene, leaving his mother to deal with the most horrific scene imaginable,” Ms Rees added.
“He must have been suffering for several hours before he died.”
The judge made it clear to the jury that Steel had not denied being involved in his brother’s death, but he claimed it was self-defence.
Darren Steel also denies assaulting two other people, in the days before the alleged incident.
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He is accused of strapping Julian Samuel to a chair using brown parcel tape and attacking him on 18 May, after Steel accused him of stealing drugs.
Steel is also said to have assaulted Dawn Michelle Begley on 20 May, when he became angry about missing drugs.
His relationship with Ms Begley was described as “on and off”.
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Darren and Martin Steel got into an argument over whether the latter had slept with Ms Begley – something they both denied.
Mr Steel told his younger brother to “stop being a prick” before he fell asleep.
The trial continues.