Staff who work in and around Stansted Airport have been taught by Essex Police to look out for signs that adults or children are being exploited.
The ease of travel into and away from London means that Stansted's air, rail and road links can be used for children being trafficked by county lines drug dealers or adults being coerced into sex work.
A team of officers, including gang and safeguarding specialists, handed out leaflets developed with the Children's Society, with QR codes directing them to information about exploitation and what to do if they suspect someone is a victim.
These were given to workers inside the airport terminal as well as taxi and coach drivers, hotel employees, and staff at car rental companies and public transport services.
This latest day of action was part of Operation Bumble, which began in October to highlight exploitation.
The operation, supported by the National County Lines Coordination Centre, is led by Detective Sergeant Mark Ghosh.
He said: "Stansted wouldn’t be thought of as a hotspot for county lines and gang activity, but you get vulnerable adults and children using the coach and rail system to transit through the airport, so it’s a chance to help those people who may have been forced to travel carrying weapons or drugs or been trafficked into the county for exploitation.
"We are victim-led, and our priority is protecting the people who are being exploited."
Christmas is a time when drugs gangs may look to entice children who would otherwise be in school with gifts or cash in exchange for transporting drugs.
DS Ghosh said: “A victim may look nervous, be carrying more than one mobile phone or have a large amount of receipts or cash they can’t explain why is in their possession.
“They may be a timid child travelling on their own or alternatively they can be quite confrontational or aggressive because they are scared.
“We’re also looking for people who appear out of place and may not know exactly where they’re going – they just know a general area."
Anyone who suspects someone is being exploited is asked to contact police.
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