Mr Sheils, 22, was shot dead shortly before 1.00am on a green area between Eastway and Bligh's Gardens and later died from his injuries in hospital. He was shot in the chest at close range.

It's emerged that his girlfriend is due to have a baby soon.

It's believed that two groups of youths had a confrontation in the Bogside area shortly before the shooting. It's understood Mr Shiels, who was working as a pizza delivery man, was with one of the groups in a chase in Creggan when he was shot.

A local man said he heard three shots and another man saw Emmett Sheils fall.

"The young fella was lying on the ground moaning and he was bleeding from his mouth," he said.

"We pulled up his T-shirt and there was a tiny hole where he'd been hit and not much blood. His eyes were open at the start but he got weaker as we waited for the ambulance.

"We kept talking to him but he went unconscious before the ambulance crew arrived and they started working on him."

The adopted sister of the victim, Maureen Wilkinson, appealed for the killers to come forward.

"The people who did this should hand themselves in for the family's sake. We don't want another family to have to go through what we are going through.

"They should go and hand themselves in so we can have peace of mind knowing that the perpetrators are behind bars. Part of our family is now missing and we will never have the same life," she said.

Mrs Wilkinson also appealed for anyone who witnesses the shooting to come forward.

"People have already been helping the police and giving them information," she said.