LONDON (Reuters) - A gang of 18 people has been found guilty of trafficking and sexually abusing vulnerable teenage girls and young women for several years in northern England, prosecutors said on Wednesday, in the latest shocking case of its kind in Britain.

The men raped or assaulted the victims after drugging them or threatening them with violence at specially-convened “parties” – often referred to as “sessions” – where they were supplied with drugs and alcohol.

Some were so inebriated they were abused while unconscious.

The offenders were predominantly Asian and aged in their 30s and 40s, raising echoes of a number of similar cases in Britain which led to accusations the authorities had feared to get involved in case they were accused of racism.

“There has been no political correctness here,” said Northumbria Police Chief Constable Steve Ashman. “These are criminals and there has been no hesitation in arresting them and targeting them using all the means at our disposal.”

“It is for individual communities to ask themselves whether they are doing all they can to eradicate such attitudes and behavior.”

Prosecutors said the gang, 17 men and one woman, had targeted 13 white girls and women, aged from 15 to their early 20s, in the city of Newcastle in northwest England between 2010 and 2014. The offenders were found guilty following four trials, the last of which concluded on Tuesday.

Three have been jailed and the others are awaiting sentence.

OPERATION SANCTUARY

Ashman said the wider police investigation into sexual exploitation in the area, known as Operation Sanctuary, was the largest and most intricate operation his force had ever undertaken. In total officers had arrested 461 people, leading to 93 convictions, he said.

“Most of the offenders are not white. They are from a really diverse section so we have people from Bangladesh, from Pakistan, from Iran, from Iraq, people who are Kurdish, Turkish, Albanian, eastern European,” he said.

Ashman also defended the decision, heavily criticized by a child protection charity, to pay a convicted child rapist about 10,000 pounds to act as an informant, saying he had helped police to prevent and detect serious crimes.

Newcastle City Council said more than 700 victims had been identified as part of Operation Sanctuary.

“We do not believe that what we have uncovered in Newcastle is unique,” said Pat Ritchie, the council’s chief executive. “Sadly, there is evidence of sexual exploitation in just about every other town and city in the country and anyone who says they do not have it are not looking for it.”

Britain has been rocked by a series of child sex abuse scandals in recent years, the most shocking taking place in the northern town of Rotherham where a 2014 report concluded that as many as 1,400 children were sexually abused by gangs of mainly Asian men over a 16-year period.

A major inquiry into historical child sex abuse, one of the largest and most expensive ever undertaken in Britain, began in February and is due to last five years.