A couple who lured a student to the UK then forced her to work in Birmingham brothels were jailed yesterday in the West Midlands' first successful human trafficking prosecution.

The 18-year-old victim, who cannot be named, was convinced in an internet chatroom that she could earn good money over the summer in a London restaurant or bar before continuing her studies at college in Lithuania.

However, when she arrived in Britain, she was forced into prostitution by Lorenc Goduni while his cohort Simona Kazakaite used what police described as "the Stockholm Syndrome" strategy to downplay the dangers.

The teenager was eventually freed by police after they were contacted by another girl.

Yesterday at Birmingham Crown Court, Goduni (27), from Albania, was sentenced to seven years for trafficking within the UK for sexual exploitation, while Kazakaite (22), from Lithuania, was given four years for conspiracy to control prostitution for gain and conspiracy to cause or incite prostitution.

The pair had denied the charges but were convicted after a trial in February this year. Judge Philip Gregory said they had shown a complete lack of remorse.

"Those who involve themselves in exploitation of traffic of teenagers must expect severe punishment, also intended to act as a deterrent to others," he said.

"She couldn't speak a word of English, she had no idea where she was and no way of getting out of her situation, into which she had been lured and was effectively trapped."

Sentencing Kazakaite, he added: "The one crumb of comfort she might have had was meeting a fellow Lithuanian who could at least have spoken to her in the same tongue and helped her out of the situation, but your role was to hold her more tightly in that network."

The victim, who spoke no English and was described by police as "very naive", was picked up by Goduni at Gatwick Airport in July 2005 and taken to his home in Ashburton Road, Kings Heath, Birmingham.

Kazakaite, who voluntarily travelled to the UK to work as a prostitute, was tasked with befriending the victim, taking her shopping for underwear and condoms, and showing her the ropes at various massage parlours.

Each morning Goduni would take the girl to various massage parlours in Birmingham, including the Garden of Eden in Yardley, and pick her up in the evening, the court heard.

During the trial, the victim said although she was not kept under lock and key she felt trapped and unable to escape as she spoke little English and did not know where she was.

The girl had been told she owed Goduni £3,500 for her flight and accommodation and was instructed by Kazakaite to hand her earnings - which totalled £2,500 for a month's work - over to him.

The victim, now studying retail in Lithuania, travelled twice to Birmingham to give evidence against the pair. She had kept the purpose of her visits secret from friends and family and gave her evidence from behind a screen.

Afterwards, Detective Constable Tom Kavanagh said they had raided the house in Kings Heath after a tip-off from another girl who had worked there.

"It appears Kazakaite told her 'It's not all that bad, once you've earned the money you can go'. She took her out to buy clothes and was like a friend. It is like the Stockholm Syndrome, where the relationship boundaries get fused."

He said human trafficking was "massively widespread" in Britain's cities, but because of the vulnerability of the women involved, and the perceived threat to their families, it was difficult to secure a conviction.

"If we don't rescue them quickly they begin to accept their lot in life."

He said the successful prosecution - which came after three other investigations into similar allegations - was thanks in the main to the victim "knowing it was right" to stand up and give evidence against the convicted pair.