People living in the Croxteth area of Liverpool have been urged to be brave in giving information which will help catch the killer of Rhys Jones.
Assistant Chief Constable Patricia Gallan, of Merseyside Police, made the appeal outside the Fir Tree pub where the 11-year-old was shot on Wednesday.
She said the community knew who shot Rhys and said she was disappointed by the public response so far.
Ms Gallan urged the youngster's killer to give themselves up to the police.
Merseyside Police say they will protect any witnesses who come forward and will guarantee their anonymity.
"We need to get this killer off the street. Within this community people know who is responsible for this crime," said Ms Gallan.
"We need your help. Come forward now and help put the suffering of Rhys's mum and dad at an end.
"Someone out there knows who committed this crime. Please tell us."
Detectives believe the murderer could be as young as 13.
Rhys was walking home after playing football when he was shot by a youth on a black BMX bicycle at a pub car park in Croxteth, Liverpool.
The youth is said to be white, aged 13 to 15, about 5ft 8in tall and wearing dark clothes and white trainers.
Rhys's mother Melanie cradled her son as paramedics battled for 90 minutes to save his life.
Two local boys, aged 14 and 18, who were arrested on suspicion of murder were released on Thursday night.
Merseyside Police have been handing out leaflets in the area with a special number for young people to text information anonymously.
Speaking at a news conference on Thursday, Rhys's mother said: "Our son was only 11, our baby.
"This should not happen, this should not be going on. Please help us."
Rhys's father Stephen said: "We have lost our world, the world has lost a good guy."
Rhys supported Everton and the club has confirmed there is to be a minute's silence in his memory before Saturday's home game against Blackburn Rovers.
Players from both teams will wear black armbands.
The club has sent a message of condolence to Rhys's family, while captain Phil Neville has joined calls for members of the community to come forward with information.
''On behalf of everyone here at Everton Football Club and the players especially, I send my condolences to the Jones family on the tragic death of their son Rhys," he said.
"We all here at Everton have families of our own and we cannot comprehend what you are going through.
"We appeal to anyone with any information to please contact the police.''
Relatives, friends and neighbours gathered at a vigil for Rhys at Emmaus Church of England and Catholic Primary School in Croxteth.
It is near the place where Rhys was shot on his way home from football training.
Tony Edge, who broke the news of the shooting to the family has also appealed for people to come forward.
He said: "Tell the police, they don't have to give their names or anything, they just have to give this person up.
"This is a little kid who went to play football, who doesn't do any harm to anyone.
"I had an image of Rhys, this little laughing boy, and my final image of him isn't that, my final image of him is him lying there in a pool of blood."
Anyone with information can text the word "crime" followed by their message to 61051.