A man responsible for running a drugs line which flooded Great Yarmouth with heroin and cocaine has been told he faces a 'substantial' prison sentence.

Norwich Crown Court heard how the county lines gang relied heavily on texts using a phone line called the Deano line to target known drug users in the town.

William Donkoh, 31, guided the conspiracy from his base in Hackney, and was found guilty of two counts of conspiracy at the court on Monday.

Duncan O'Donnell, prosecuting, said that Donkoh helped run one of the main county line drug operations using a network of 'enforcers' and 'minions'. Police say it is estimated that 45,000 text messages were sent by the line between May 2017 and June 2018.

Also convicted following a six-week trial was gang member Sebastian Arenas-Valencia, 20, from Hackney, who was involved in the 'management and enforcement' of the operation.

Tatjana Reinis, 40, of Rodney Road in Great Yarmouth, and Irina Rasimovic, 31, of no fixed address, were also convicted on both conspiracy charges, with their roles described as 'runners' in the operation.

Ian Starkings, 38, of Pottergate, Norwich, was found not guilty of the two counts of conspiracy and was released from the dock.

Donkoh's barrister Philip Misner said Donkoh said he wanted to be sentenced 'sooner rather than later'.

The case was adjourned until Wednesday, April 10, when the four defendants will be sentenced along with other gang members who have already pleaded guilty. It is expected to last two days.

Judge Andrew Shaw warned the defendants they all faced 'substantial' sentences for the conspiracy.

Judge Shaw also thanked the jury, who were out for more than 14 hours considering verdicts in the case.

During the trial the court heard how Donkoh was in charge of the main drugs line and was seen topping up a phone near his home in Hackney, which was then used to send out mass texts.

Norfolk police Tactical Team lead the investigation and discovered Donkoh was running the line with a single mobile phone, acting as a call centre for his network of drug runners in Great Yarmouth.

Call data later seized by officers revealed that text messages would be sent out daily from the dealer number advising customers they were around with the 'best of both' which was code for heroin and crack cocaine being offered for sale in the town.

Once drug users placed their orders, managers such as Arenas-Valencia, who were already in Yarmouth, would supply and control the local drug runners.

Donkoh would contact the managers who then in turn would direct the local runners to where they would be working that day. The managers would also ensure drugs were not stolen and any cash was not lost before taking it back to London.

It is estimated that 45,000 text messages were sent by the line between May 2017 and June 2018.

On Wednesday, October 25, 2017, officers executed warrants at Priory Plain, Wellesley Road, and Orford Close where mobile phones and Class A drugs were seized.

Detective Constable Carl Carter, who led the investigation under Operation Gravity, said: 'This case is a prime example of how a county line operates and by securing these convictions we have stopped a dealer group who played a significant role in class A drugs supply in Great Yarmouth for five years.'

After making the arrests further enquiries led to the arrest of Donkoh.

He added: 'This isn't just about drug supply. These groups do exploit vulnerable people who then become criminalised and by targeting those in control of these lines we can help prevent this from happening in the future.'