BANGKOK, Thailand: More than 5,300 people are still stuck in online scam centers near Myanmar's border with Thailand, a human rights group has said.

This is more than a year after thousands of people were freed during a joint crackdown by several countries in the region.

In a letter dated June 22, the Civil Society Network for Human Trafficking Victim Assistance (CSNHTV) asked Thai police to act. The group said many of those still trapped are foreign nationals being held at four locations in areas controlled by a Myanmar militia.

The group estimates that the trapped people include about 1,600 Chinese nationals, around 200 people from Myanmar, 20 Thai citizens, and others from countries such as the Philippines, Taiwan, Malaysia, Brazil, Russia, Kenya, Uganda, Rwanda, and Zimbabwe.

Scam centers in Southeast Asia, including those in Myanmar and Cambodia, run illegal online operations that cheat people around the world and make billions of dollars every year, according to the United Nations.

Many of these centers, especially those along parts of the Myanmar–Thai border, are run using workers who were trafficked there by criminal gangs. These people are often forced to work in harsh conditions and face abuse.

Last year, Thailand led a regional effort to shut down scam centers along its borders and rescued about 5,000 people from large scam hubs in Myanmar's Myawaddy area. However, these illegal operations have continued on a large scale.

In its letter, CSNHTV said many victims are still being held in scam compounds located in areas controlled by the Democratic Karen Buddhist Army (DKBA) militia in Myanmar.

The group said that many of these compounds have not yet been shut down or searched to rescue all the remaining victims.

Because of this, the criminal groups continue to carry out online fraud and human trafficking, harming people around the world, especially in the United States and Europe.

Two officials from the DKBA did not respond to requests for comment. A spokesperson for Myanmar's military-backed government, which has said it is cracking down on scam operations, also did not immediately reply to questions from Reuters.