A string of brothels set up across East Anglia operated as a 'family business' bringing in hundreds of thousands of pounds over a two-year period, prosecutors said yesterday.

Norwich Crown Court heard how the sex dens had been set up between 2006 and 2008, fronted by seemingly respectable businesses at the Cavendish Hotel in Princes Road, Great Yarmouth, and a Chinese herbal medicine shop in Upper Orwell Street, Ipswich.

A third brothel operated our of a residential property in Chalk Hill Road, Norwich.

Opening the trial, prosecutor Hugh Vass said that suspicions first arose when advertisements for 'Chinese and Oriental massage' were placed in newspapers. Financial investigators later found that brothel operators spent �10,000 on advertising over the two years.

When undercover officers responded to the adverts, they were told they could pay �60 per half hour or �100 per hour for sex with 'beautiful young Asian women'.

Shu Quin Wang, 54, of Princes Road, Yarmouth, has admitted conspiracy to manage brothels. Her brother, Jian Zhane Wang, 52, of the same address denies conspiracy to manage brothels and money laundering.

Pin Yo Wang, from Newport, who is no relation, has also admitted conspiracy to operate brothels.

Mr Vass said: 'This investigation came about as a result of a people trafficking operation, although in this case there is no evidence that these women were enslaved or coerced into prostitution.

'The setting up and running of brothels in East Anglia was the Wang family business. When you add up the totals over the years, the business brought in hundreds of thousands of pounds.'

Jian Zhane Wang denies all knowledge of the brothel operation. He lived at room four in the Cavendish Hotel while a brothel operated out of the adjacent room five, Mr Vass said.

The hotel had been bought at a cost of �300,000 using a mortgage based on salaries far higher than the Wangs declared to Her Majesty's Revenue and Customs.

Jian Zhane Wang bought the house in Norwich for �202,000. He told the tax office he earned less than �15,000 a year but he could afford to pay the �1,400 a month mortgage on the property.

He told police he had let the house but could not name the tenants or say how much they paid. He said: 'Maybe �500 or �600 a month.'

He ran his Chinese medicine business from the property which housed the Ipswich brothel.

But in his police interview, he said: 'I am not involved in any of it and don't know if they have that kind of activity there or not.'

Det Con Jane Woods read out excerpts from his statement, in which he gave a string of no comment answers and said he did not know what a brothel was.

Mr Vass said: 'How could he fail to notice what was going on?'

He added that the Wangs' intention had been to pay off mortgages using their income from prostitution and then sell the houses meaning 'the profit would be disassociated from its murky, criminal origins'.

Police raided the Norwich brothel in December 2007 and raids in Ipswich and Yarmouth followed on Chinese New Year in February 2008.

During the raids a number of prostitutes were discovered inside the properties and police surveillance showed a large number of men visiting each address.

Shu Quin Wang had denied the charge but changed her plea to guilty on Monday.

The trial is expected to last about one week.