On the opening day of the trial of the nine men, a court heard how seven teenage girls, the youngest of them is 13 years old, were groomed into child prostitution with offers of alcohol, drink and cash by nine men in a sex-trafficking ring.

As the trial started the prosecution revealed how some of the girls were sold on to other men to be abused, and one 15-year-old girl was plied with drink, drugs and cigarettes to persuade her to have sex with others as a "favour" to her "pimps", the prosecution said.

Deborah Gould, prosecuting, warned the jury that as the trial unfolded they would be introduced to a world "that I expect few of you were aware of".

Apparently most of the girls involved thought "to be loved and in love" with the men at the time.

The men, who are aged between 21 and 59, including a group of three brothers, operated mainly around the small town of Wellington, near Telford and face a total of 55 charges including rape, child prostitution, sexual activity with a child and trafficking children within the UK.

"This case is about exploitation," said Debbi Gould, prosecuting. "The Crown say that the men in the dock variously trafficked, raped or sexually abused girls both over and under the age of 16 years over a considerable period of time."

Three of the men, brothers Ahdel Ali, 23; Mubarek Ali, 28; and Tanveer Ahmed, 39; are accused of acting as "pimps" and exploited their victims. Others, including Abdul Rouf, 34, and the oldest defendant Mohammed Younis, 59, used their homes as brothels to allow men to engage in sexual activities with the girls, the court heard.

Jurors were told the men usual tactics to entice the girls revolved around offers of car rides, employment and cash, before they started grooming and exploiting them either for their own sexual gratification or to earn money. Some of the girls were treated as sexual commodities as they were sold or "given" to other males.

Two girls, who cannot be named, were "slowly but surely" persuaded by the brothers through a combination of attention, gifts, encouragement, pressure and guilt to have sexual activity with others for their benefit, the prosecutor told the court.

"Having established that their victims were prepared to accommodate that to please them, the next logical step was to encourage them to do this for payment," Gould told the jury.

"Pimps, for that is what the Crown says that Ahdel Ali, Mubarek Ali and Tanveer Ahmed are, identified and then exploited their victims' need for attention and protection."

On one occasion, the men, assisted by Noshad Hussain, 20, are said to have used one girl as a child prostitute and transported her to different locations to meet men.

At the time they provided the victim with plenty of drinks, cannabis and cigarettes and pressured her into have sex with others as a "favour" to them.

The court also hear how on a different day, she was allegedly driven to a park in Stoke-on-Trent to meet a man from Bradford to perform oral sex.

"They sold her as a sexual object to others," Gould said. "She was acting as a child prostitute, they were controlling and organising her activities ... and transporting her to different locations in order that she could undertake these activities."

Meanwhile details of how two of the girls were groomed in a churchyard in Telford where young Asian males congregated to drink and smoke also surfaced.

One 15-year-old is also alleged to have performed oral sex on Mohammed Ali Sultan, 24, on three occasions.

The jury members were warned that what they were likely to be distressed by some of the evidence in the case.

"You will neither like nor be impressed by the behaviour, attitudes and morals of some of the defendants in this case, most of whom are married men," said Gould.

"The Crown says that just as the defence will accuse the girls of telling lies, so too have the defendants lied.

"Don't be bamboozled, don't be confused and don't be misled. The psychology of abuse and our understanding of it has greatly changed in recent years."

Ahdel Ali, 23; Mubarek Ali, 28; Tanveer Ahmed, 39; Mohammed Ali Sultan, 24; Noshad Hussain, 21; Mohammed Islam Choudrey, 52; Marhoof Khan, 33; Mohammed Younis, 59; and Abdul Rouf, 34; deny all the charges against them.

The case continues.