A FATHER and son have gone on trial accused of falsely imprisoning a teenager and giving him an electric shock because he refused to sell drugs for them.

Trevor Anthony Thirlwall, 53, and Trevor Peter Thirlwall, 30, are also said to have blackmailed the boy's stepfather when he ran up drug debts - threatening to kidnap his wife and chop off her fingers.

Teesside Crown Court heard that Mark Devonport and his stepson Robert Phillips, then aged 16, were recruited by Mr Thirlwall Snr to sell cocaine in the South Bank area of Teesside in 2002.

They received deliveries of an ounce of the drug from a go-between and had to provide their suppliers with £1,600 to get another supply once it had been sold on.

Christopher Attwooll, prosecuting, told the jury Mr Phillips plucked up courage in October 2002 to tell the middle-man he no longer wanted to be involved.

He said Mr Phillips went to see a friend of his mother's at The Commercial pub in South Bank, one of several licensed premises owned by Mr Thirlwall Snr, and was assaulted. He said Mr Thirlwall Jnr held a stun gun to the teenager's side.

Mr Attwooll claimed Mr Devonport was approached by Mr Thirlwall Snr in May 2002 and after initially refusing to sell drugs "reluctantly agreed" because he was afraid of him.

The prosecutor claimed Mr Devonport got behind with payments and was threatened by Mr Thirlwall Jnr.

Mr Attwooll said: "He could not raise the money, but he believed the threats would be carried out. He did the only thing he could do and went to the police."

Mr Thirlwall Snr, of Granville Road, Middlesbrough, and his son, of Southwark, London, deny charges of false imprisonment and causing actual bodily harm on Mr Phillips and blackmail against Mr Devonport.

Mr Phillips gave evidence via a video-link, and under cross-examination, Mr Thirlwall Snr's barrister, Robert Terry, claimed his allegations were "nonsense".

The trial continues.