Drugs weighing three-quarters of a tonne, an arsenal of deadly weapons and over £500,000 in cash have been seized in the war on county lines gangs using the train network.
British Transport Police’s specialist Taskforce made 630 arrests, with 50 networks closed down in the year to April.
Criminals exploit children to courier crack, cocaine, heroin and cannabis from places like London to smaller UK towns and cities.
Some youngsters are exposed to physical, mental and sexual abuse and often trafficked a long way from home.
Police have been safeguarded hundreds of them with the help of charities and local authorities.
Fourteen adults are charged with modern day slavery offences, a force spokesman said.
Isaiah Taitt, 23, of Chatsworth Road, Hackney, and two others appeared at Warwick Crown Court on Friday accused of moving children from London to Northampton and requiring them to “perform forced or compulsory labour”.
Taitt is also said to have been concerned in the supply of crack cocaine and heroin.

Detective Superintendent Craig Payne, who leads BTP’s County Lines Taskforce, revealed in the past year his officers had identified 68 addresses that had been taken over by the drug gangs in a process known as cuckooing.
Around 789 kilos of Class A, B and C drugs, £540,000 in cash and 180 knives and guns were seized.
Earlier this month, county lines dealer Elijah Henry-Gooding, 27, was jailed for 38 months after undercover officers caught him with 100 wraps of crack cocaine and heroin he was supplying to customers around Richmond station.
Henry-Gooding, of Tavistock Avenue, Ealing, had a folding lock knife concealed internally, £1,200 in cash and a Nokia burner phone running the line.

Det Supt Payne added: “Consistent results like these show we are making great strides in the fight against county lines gangs and the communities they prey upon.
“But we know there is still more work to be done and far from being complacent, we are committed to intensifying our efforts to intercept the transport of drugs on the rail network.
“We are constantly evolving and enhancing our methods to keep pace with the tactics used by these gangs - teaming up with Home Office forces means we can pool our resources and intelligence to target our deployments.
“We will continue to pursue those who make lives a misery through drug supply particularly those who control children and young people and exploit the vulnerable.”
Anyone concerned about county lines activity can text BTP on 61016, dial 0800 40 50 40 or call independent charity Crimestoppers anonymously on 0800 555 111.