Four people have been charged with drug dealing and trafficking teens to Brighton, the British Transport Police (BTP) said.
The BTP found a 13-year-old and a 14-year-old boy at Brighton railway station in June last year as they tried to head back to London without tickets.
The force said that the ensuing investigation led to 16 “modern day slavery” charges being brought.
The BTP said: “Following an extensive county lines investigation, British Transport Police have charged three boys and one man with modern slavery charges.
“One 16-year-old boy, from Warrington, two 17-year-old boys, from north London and Southend, and 21-year-old Declan Sherriff, of Varley Drive, Twickenham, were arrested in June and August 2022 for drug supply and modern day slavery offences and served with charges on Wednesday 20 September.
“In June last year, two teenagers aged 13 and 14 were found at Brighton Railway Station trying to return to London without tickets.
“They had been reported as missing and were believed to have been exploited by county lines gangs.
“A complex investigation, concerning a conspiracy to supply class A drugs and the human trafficking of children via a county line from London into Brighton, resulted.
“And just nine days after the teenagers were found, arrest warrants were successfully executed.”
Detective Superintendent Gareth Williams, head of the County Lines Taskforce, said: “Achieving 16 modern day slavery charges through a single investigation represents outstanding work by my officers.
“These charges have almost doubled the number we had achieved since the taskforce was established in 2019, bringing our total to an impressive 38 modern slavery charges connected to illegal drug supply.
“Successfully securing criminal charges for such serious offences is down to the dedication of my officers and their tenacity in seeking justice for the two exploited teenagers that we found in Brighton last year.
“Ensuring those involved received critical safeguarding interventions and support, my team demonstrated that it is dedicated to identifying vulnerability and ensuring the safety of all, across the rail network.
“These charges are a significant step towards disrupting county lines activity and demonstrating that the railway network will always be a hostile environment for drug suppliers to operate in.”
Hopefully they get rehabilitation. Young children should be swimming in the sea, riding bikes, kicking a ball in their gardens and enjoying bbqs – not selling drugs! So sad!