A teen who admits stabbing an 18-year-old in a Dublin park melee allegedly told him: "You don't know who stabbed you," the Central Criminal Court has heard.
A witness, giving evidence by video link, told the prosecution there was "chaos" with "everyone just fighting each other" but the melee suddenly stopped when someone shouted "knife".
He said he saw Azzam Raguragui (18) running up a hill with the accused behind him holding a knife in his right hand.
He added that Azzam slipped and fell on his back and the accused stood over him.
Mr Raguragui tried to push the accused away with his legs, the witness said, adding: "The accused hit him to the leg once and then he came down with a swinging motion towards his chest area with the knife."
The witness said he had a vivid memory of the incident and dreams about it every night.
Following the fight, he said, he remembered one of the teenagers saying to the accused: "What the f*** are you doing?" before the accused, with the knife still in his hand, saying to Mr Raguragui: "You don't remember who stabbed you."
The witness added he thinks the accused then ran away.
The 17-year-old accused, who cannot be identified because he is a minor, has pleaded guilty to manslaughter but not guilty to the murder of Mr Raguragui on May 10, 2019, at Finsbury Park, Dundrum, Dublin 14.
Under cross-examination the witness told the defence the fight broke out after someone, but not the accused, punched Mr Raguragui during a conversation about a stolen bicycle.
A second teenage witness told the prosecution how earlier that day Mr Raguragui approached two members of the other group looking for a bike that had allegedly been stolen.
There was no aggression during that conversation, he said, and when the other group said they did not have the bike they went their separate ways.
The witness was with Mr Raguragui and others in Finsbury Park that day at about 7.50pm when he saw members of the other group approaching.
He said he presumed they were coming to return the bicycle "to resolve the situation".
The witness remembered the accused asked who was looking for the bike and Mr Raguragui responded. Words were exchanged, but the witness felt the accused was not aggressive but was confrontational.
He said that he told the other group: "If we get the bike back everything is grand. We go our separate ways."
At this point the witness did not believe there would be any problem between the two groups and he was leaving the park on his bicycle when the fight broke out.
The witness ran towards it and was involved in the fight when he heard someone shout "knife" and everyone suddenly stopped.
He said he left at that point, not knowing that his friend had been stabbed.
The trial continues in front of Mr Justice Paul McDermott and a jury of six men and six women.