Garda John Santry, who was one of the first gardai at the scene of the murder of Toyosi Shittabey, told prosecuting counsel Mr Brendan Grehan that several times he had to ask the group to step away from the body of Toyosi while gardai and ambulance crew attended to him.
It was day five of the trial of Michael Barry (26) of Pigeon House Road, Ringsend, in Dublin 4, who has pleaded not guilty to the murder of Nigerian teenager Toyosi Shittabey (15) on April 2, 2010, at The Boulevard, Mount Eustace in Tyrrelstown, Dublin 15.
Barry has also pleaded not guilty of producing a baseball bat in the course of a dispute.
It is the prosecution's case that Michael's brother Paul, who is now deceased, inflicted the stab wound on Toyosi but that Michael was an accessory to the murder, following what has been described as a row with racial undertones.
Garda Santry said he saw a young black teen lying on the roadside with his body on a grass verge and his legs on the road. "There was a number of young black males and young white females around him and people there were getting agitated and angry," said Garda Santry.
He said he and a number of other gardai and an off-duty nurse commenced CPR on Toyosi but that he was non-responsive. He said later in the evening a large group of black teens tried to gain access to James Connolly Memorial Hospital where Toyosi was brought after the stabbing.
Under cross-examining by defence barrister Ronan Kennedy, Garda Santry agreed that some of the black youths were "interfering with attempts to resusitate" Toyosi at the scene.
"I think some tried to help by placing something over the wound but on several occasions we had to ask them to step away and they were highly agitated," said Garda Santry.
He said the youths had to be "forcefully removed" from the hospital and emergency assistance was called when they refused to leave. He said that although some of the events at the hospital were captured on CCTV, he was not sure whether some of the black youths became involved with someone else in the waiting room.
Garda Kevin Woods gave evidence that later in the night a large crowd gathered outside the house of Paul Barry's in Mount Garrett Rise, including a number of black youths.
"These people were aggressive and in a distressed state but they eventually moved on after garda intervention," he said.
Garda John Mulcahy said a similar group attempted to gain access to Mount Garrett Rise the following morning.
A brother of Paul Barry's partner Colette has told counsel he received a call from his sister to attend her house at Mount Garrett Rise.
Brian Murphy said as he drove along The Boulevard he saw gardai and a boy "who looked like he was asleep" lying on the roadway. He said when he got to his sister's house he had a conversation with Michael and Paul Barry and he noticed Michael had red scuff marks on his head.
"They told me to go around and get the gardai and bring them back to the house as Michael had mentioned his phone was stolen and they were beaten up," said Mr Murphy.
He said he drove around to The Boulevard and asked gardai to follow him back to the house where gardai spoke with the Barry brothers.
The trial continues.