A teenager was stabbed to death after rival "postcode" gangs clashed at a party, witnesses said.

A gang of up to 40 youths armed with baseball bats and knives fought running battles in the street in Sheffield on Saturday night, it was claimed.

Emergency services were called to Rokeby Drive, Parson Cross, just after 11pm following reports an 18-year-old man had been assaulted "by a number of people".

Witnesses said they saw the victim staggering in the street before he collapsed to the ground in a pool of blood.

He was taken to hospital in the city but died from his injuries, South Yorkshire Police said.

Two youths, aged 16 and 17, are being held on suspicion of murder.

Witnesses said a fight started in the street between rival gangs from Sheffield's S6 and S5 postcodes following a party celebrating a 16-year-old girl's birthday.

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