Rappers such as Busta Rhymes have a large following on MTV

Two police officers were injured amid pushing and shoving as thousands of people crowded the streets outside MTV's studios in central Manhattan.

Four people were arrested and charged with disorderly conduct.

MTV apologised for postponing the MC Battles rapping contest but said it was unavoidable.

Dave Sirulnick, the network's executive vice president of news and production, said: "We're disappointed we had to take this measure, but we'll announce details about rescheduling MC Battles shortly.

"We apologise to anyone who travelled far or waited for a long time for the contest, but we'll provide information soon about future plans."

The two injured police officers were treated at a hospital and released.

Thousands of people had lined up overnight and in the early morning outside MTV's studios at 44th Street and Broadway.

The contest - for ability in "freestyle" rapping - was organised by the station and the Def Jam record label to mark MTV's hip-hop week.