A team of six solicitors has just returned from a two-week mission to free Indian slaves, organised by an international charity.

The lawyers used their legal skills to help victims of bonded labour in Chennai in southern India, working with a team from International Justice Mission (IJM).

The solicitors posed as a television crew to infiltrate one bonded labour camp, as well as preparing documents and evidence to present to the prosecution authorities.

One of the lawyers, Christine John, international secretary for the Lawyers Christian Fellowship, said: 'We went into a quarry to interview a money-lender we knew was using bonded labour, pretending to be making a documentary about business in India.

I posed as the presenter and asked questions about the conditions of workers.

The money-lender was very suspicious, but we did succeed in distracting him while some members of the IJM interviewed the workers and got signed affidavits from them without their captor being aware of it.

'The whole team had covert cameras as well as the official ones.

Some of what the money-lender said to us will be very useful to the prosecution's case against him.'

The bonded labourers in the camp are expected to be freed by the authorities within a few weeks.

The lawyers also attended a bonded labour trial and were invited by the judge to tell them what they thought of the trial afterwards.

Guildford-based criminal lawyer Mark Williams, of Mark Williams Associates, said: 'We were very polite, but we made it clear that we thought they needed to be a lot tougher in prosecuting these cases.'

Slavery was outlawed in India in 1976, but there are millions of uneducated workers trapped in bonded labour and unaware of their rights.

Some have spent a lifetime working as slaves to money-lenders, paying off loans as small as 20.

'The presence of UK lawyers raises the profile of this problem with the Indian authorities,' said Mr Williams.

'It is also a practical help - as a criminal lawyer, I was able to help with [the IJM team's] questions on jurisprudence because the legal system there is very similar.'

The IJM will have eight places available for lawyers from the UK next year.

All the lawyers involved this year were members of the Lawyers Christian Fellowship.

Rachel Rothwell