BBC Panorama: Following the police taking on UK drug gangs
For a year, Panorama followed Kent Police as it tried to disrupt networks of dealers, known as "county lines", that transport drugs worth millions of pounds from London to towns across their county.
The BBC filmed as officers arrested street dealers and raided the homes of those believed to be involved.
BBC Panorama, Drugs, Cops and Lockdown, will broadcast on BBC One on Monday 10 May at 19:30 and then be available on BBC iPlayer.