A man aged 18 has been killed in what is understood to be the latest outbreak of so-called "postcode" gang violence in Sheffield.

The victim, named locally as Dale Robertson, died in hospital after a confrontation on Parson Cross, a large council estate in north Sheffield.

A police spokesman said last night that a post-mortem examination revealed the victim died as a result of stab wounds to the chest.

The incident happened on Saturday night and the presence of a large gang in the Rokeby Drive area alarmed residents to the extent that police were called by one who did not even realize there had been a serious stabbing.

Police have not officially released an identity for the man but it is understood he was visiting the area to attend a birthday party.

Three youths, one aged 16 and two aged 17, have been arrested and last night remained in custody as officers worked to piece together details of the incident.

So far the force will say only that they were called around 11pm and believe there had been a disturbance outside a house.

Yesterday, a large section of the street remained cordoned off as police experts began a painstaking search for possible evidence.

One resident told the Yorkshire Post: "I called the police because there was such a big gang in the street.

"We have trouble around here with kids anyway, but this was really big. We turned the television down to listen and went upstairs to have a look because we couldn't see much from downstairs.

"There was a really big group in the street and it was very noisy.

"This morning we could not even leave the house to go to church , because it was a crime scene," she said.

Those living in the area suggested there had been a confrontation between two groups which identify themselves as S5 and S6, using postcodes as a form of gang name.

One teenager, part of a group which gathered to leave flowers in the street, said: "It all started after a bit of banter and name calling between the two gangs. One of them walked off to go home and then they all started fighting.

"I was invited to the party but I went ice skating and now I'm glad I did.

"About 40 people were involved in the fight, some were carrying baseball bats and knives.

"It lasted for about 10 minutes before the cops were called.

"At one point two cars came screeching up the street and you could hear them being trashed. You could hear them being kicked and I think one of the windscreens was smashed in.

"The lad (the victim) managed to walk off before he collapsed on the ground.

"You could see the blood on the street this morning but the rain has washed it away now."