THREE men and a 17-year-old youth have gone on trial in Middlesbrough accused of grooming and sexually exploiting vulnerable underage girls.

Prosecutors claim the accused gave the girls drugs and used threats and intimidation to get what they wanted.

Outlining the case for the prosecution at Teesside Crown Court this morning, Christopher Knox said the defendants used Facebook and Blackberry messaging to keep in touch with the girls.

He said: "This case we say involves the exploitation of a group of young girls by a loosely connected group of young men.

"These young men are about three or four years older than the girls, we say on behalf of the prosecution, that they preyed on."

The court heard the men were charged with 18 offences.

The men are charged with various offences, including sexual activity with a child, child abduction and causing or inciting a child to engage in sexual activity.

Prosecutors claim seven girls, all aged between 13 and 15, were manipulated by the defendants for their sexual gratification.

"Most of the cases are an allegation of a crime called sexual activity with a child," Mr Knox said.

"These are sexual activities with girls who are almost without exception vulnerable for one reason or another and who have, in almost all cases, been groomed by these young men and sometimes passed around from one to another.

"The prosecution say this is not a girlfriend boyfriend relationship - it is an exploitative relationship which we call grooming."

Judge John Walford earlier told the jury of ten women and two men they should decide the case on the evidence heard in court.

He added: "These are the sort of allegations which tend to arose emotions - allegations of sexual activity towards children.

"Comparisons may be drawn with other cases were other sexual allegations have been made in other towns and cities in this country, cases which given rise to public debate and discussion.

"For reasons which I hope are obvious, not least because you must decide the case on the evidence and only the evidence, it's important that you dismiss any views which you may have heard or you may have thought about what happened in other towns and cities involving different groups of people."

Shakil Munir, 32, of Tollesby Road, Middlesbrough, is charged with four counts of sexual activity with a child and child abduction against two girls aged 13 and 14.

Junaid Butt, 18, of Kensington Road, Middlesbrough, is charged with sexual activity with a child and arranging or facilitating commission of a child sex offence. His two alleged victims were aged 14 and 15.

Ibrar Mahmood, 18, of Breckon Hill Road, Middlesbrough, faces four charges of sexual activity with a child and three of causing or inciting a child to engage in sexual activity. The charges relate to two girls both aged 14.

A 17-year-old male youth, who cannot be named for legal reasons, is charged with three counts of arranging or facilitating commission of a child sex offence. His three alleged victims were aged 14.

All four defendants deny all charges.

A fifth defendant, Sakib Ahmed, 18, of Cambridge Road, Middlesbrough, has admitted five charges of sexual activity with a child. The charges relate to five girls, one aged 13, three aged 14 and one aged 15.

The trial is expected to last up to four weeks.