Justin was due to start a college course in September

Justin Maynard was shot in the neck in Tugford Close at about 1845 BST on 26 August.

Patrols have been stepped up and stop-and-search tactics reintroduced since the shooting.

But Greater Manchester Police (GMP) said their best lead was a woman who contacted them with "vital information" shortly after Mr Maynard's death and have appealed for her to get back in touch.

His mother, Miranda, said: "I lost everything on the night Justin was killed, he meant the world to me and I can't imagine my life without him.

'Life turned upside down'

"Our family will never be the same without him and we all miss him terribly.

"If anyone knows anything about his death I would ask them to please, please come forward and tell the police what they know.

"I lost my whole world the night that he was killed and it's not fair that his killers should live a normal life when mine and the rest of my family's have been turned upside down."

She added that her son had "wanted to make something of himself" and was due to start a college course later this month.

Leaflets written in a variety of languages and posters of Mr Maynard have been distributed around Moss Side in the hope they will jog peoples' memories of the incident.

Detective Superintendent Vincent Petrykowski, of GMP, also appealed for the woman who contacted them at about 1300 BST on 28 August to speak to detectives again.

He said: "This woman has not been in touch with us since and we are very eager to speak to her again.

"I would ask her to please call the incident room as soon as possible."