The violence only succeeded in causing fear and alarm to innocent visitors to the event

Police spokeswoman

A West Yorkshire Police spokeswoman said of the violence: "Police officers wearing protective equipment were deployed to key areas to support event security staff.

"Further police resources were brought in and order was restored by 3.30am.

"Officers came under attack with stones and other missiles. Thirteen officers received minor injuries and some police vehicles were damaged."

Nine people were arrested during the disorder, which was contained within one campsite.

Fifty arrests

Police said a crowd of about 200 other people showed their support for the group's actions, which led to three toilet blocks being set on fire.

A spokeswoman said: "The violence only succeeded in causing fear and alarm to innocent visitors to the event."

Police said an inquiry had been launched to identify the culprits.

During the three-day event at Temple Newsam, thousands of rock fans saw headline acts including Eminem, Marilyn Manson, Green Day and Travis.

Police said 200 crimes were committed over the weekend and 50 people were arrested for a variety of offences including violence, theft, drunkenness and possession of drugs.

Meanwhile police in Berkshire are still hunting two men in connection with the rape of a 16-year-old girl in her tent at the Reading music festival on Sunday.

Thames Valley police reported a total of 80 arrests at the event, mostly connected with drug-related offences.

Later 32 people were charged and 24 cautioned. Six offensive weapons were seized.