Five years ago, the land now home to KK Park – a vast, heavily guarded complex stretching for 210 hectares (520 acres) along the churning Moei River that forms Myanmar’s border with Thailand – was little more than empty fields.

Set against rugged mountains south of the town of Myawaddy, KK Park, with its on-site hospital, restaurants, bank and neat lines of villas with manicured lawns, looks more like the campus of a Silicon Valley tech company than what is really is: the frontline of a multibillion-dollar criminal fraud industry fuelled by human trafficking and brutal violence.

Myanmar, Cambodia and Laos have in recent years become havens for transnational crime syndicates running scam centres such as KK Park, which use enslaved workers to run complex online fraud and scamming schemes that generate huge profits.

There have been some attempts to crack down on the centres and rescue the workers, who can be subjected to torture and trapped inside. But drone images and new research shared exclusively with the Guardian reveal that the number of such centres operating along the Thai-Myanmar border has more than doubled since Myanmar’s military seized power in 2021, with construction continuing to this day.