The teenager accused of murdering Kellon Hill insisted to a jury that he did not stab him.

Kellan Lewis admitted getting into a fight with the 18-year-old victim, but denied using a knife against him.

Mr. Hill, a college student, died from a stab wound to the heart after trying to retrieve a gold chain that prosecutors say Lewis snatched from around his neck.

The ensuing fight is said to have involved four of Lewis's friends. The alleged murder took place at a party for a 14-year-old girl at Elbow Beach in August 2008.

In answer to questions from defence lawyer John Perry QC, Lewis said he had no animosity towards Mr. Hill but had had a previous run-in with his cousin, Diondea Symons.

Lewis,18, said he saw Mr. Hill and his cousin about to get on a bike and leave the party that night. He spoke to Mr. Hill, and made a "joke" that Mr. Symons was a sissy.

According to Lewis, Mr. Hill replied: "He's not a sissy. You're a sissy."

Lewis went on to tell the jury: "I thought he was joking with me, so I joked back 'that's not what your momma said last night'. And then he [Hill] just spat in my face. I tried to pull him off the bike. I used my left hand and just gripped him in his chest like, as I was trying to pull him off the bike."

He explained the chain Mr. Hill wore around his neck broke loose and dropped to the ground — but denied he was trying to steal it.

Lewis went on to describe turning his back on the situation and heading downhill away from the scene at "a slow jog" when he heard two cracks. He turned to see Mr. Hill "smashing" his friend Gary Hollis with a helmet.

At this point, he said, the "situation got ugly" and a number of people started hitting Mr. Hill. When the fight came down the hill he said Mr. Hill "gripped' him and he punched him twice in the head.

Lewis said the crowd moved back up the hill and he noticed his own gold chain was missing from around his neck. He said he had no further contact with Mr. Hill, and left the scene, but later noticed someone lying down up the hill and heard a lady say someone was bleeding.

"Did you use a knife on him?" inquired Mr. Perry.

Lewis replied: "Not at any time did I use a knife on him."

However, prosecutor Rory Field accused Lewis of lying. He suggested he'd been acting aggressively that night, in a manner inappropriate for a young girl's party. Lewis denied this.

Mr. Field went on to accuse him of making up the story about the exchange of words beginning with the "sissy" comment.

"What really happened was you went up and grabbed his chain, probably worth a lot of money," alleged the prosecutor.

Lewis denied this.

"You grabbed that chain. This whole little backwards and forwards story about his mother, you just made that up. You grabbed that chain. You were either stealing it or you were showing your contempt for him or your power that evening by tearing it off," alleged Mr. Field.

"No," replied Lewis.

"Presumably you thought he'd be an easy mark," continued Mr. Field. "And you were picking on him because he was a nice guy."

Lewis denied that too.

He had been asked earlier by Mr. Perry about hand signs he and his friends made in photographs taken at the party. Lewis explained these represented abbreviations for place names in the White Hill, Sandys, neighbourhood where he and his friends live. He explained, for example, that when he made a "W" and an "L" with his fingers, this represented Woodlawn Road.

However, Mr. Field challenged this, suggesting to Lewis: "You were imitating or were trying to make what you thought were gang signals."

"No," replied Lewis.

"And let me tell you the relevance of that. Because you were being scary, weren't you?" suggested Mr. Field.

Lewis denied the suggestion. He is on bail, and the case continues.