A crude but deliberate strategy of slaughter and arson has been unleashed by Myanmar’s military across the rural north-west of the country. Terrorised communities are being woken by machine gun fire. Soldiers descend on the selected village. People are interrogated, beaten, tortured and killed. Sexual violence is routinely used. Homes are searched, looted and burned. Survivors are forced to flee their smouldering homes for the jungle.

The military, or Tatmadaw as it is known, is notorious for these “scorched earth” campaigns. The armed forces attacked Rohingya villages in this way in northern Rakhine state in late August 2017, forcing three quarters of a million people to flee their homes in a matter of weeks. But I could also be describing the same military’s attacks on the Kachin in north-east Myanmar, or on the Karen in the south-east in the 2000s, or on the Shan in the 1990s. The list goes on.

The objective is to terrorise, punish and destroy any community thought to have links to groups opposing the military. These include ethnic armed groups defending their right to self-determination, and now the nationwide democratic movement resisting military rule following the attempted coup in February.

Myanmar’s borders to the north, east and west are packed with millions of refugees of these brutal campaigns, the vast majority of them from Myanmar’s ethnic and religious minorities. Many have spent close to their entire lives in refugee camps, unable to return to their homelands as the Tatmadaw’s violence continues. Others have arrived in the past few months, and their numbers will keep rising.

A massive scorched earth campaign is currently underway in north-west Myanmar. Thantlang town in Chin state has been the worst hit so far, with images of smoke billowing from the hilltop town shocking social media – just as scenes of burning Rohingya villages did four years ago. Alarming levels of troop deployments indicate that the full scale of this new operation could be unprecedented.

The military’s widespread and systematic attacks on civilian populations are crimes against humanity and war crimes, and may even amount to genocide. They continue to escalate because no one is stopping them.

As UN special rapporteur on human rights in Myanmar, I repeatedly called for the leaders of the Tatmadaw to be brought to justice in international courts, because Myanmar’s own justice system is unable to hold fair proceedings and deliver accountability. The high-profile charging and sentencing of journalist Danny Fenster this week (he was subsequently freed today), along with all arbitrary detention, sham trials and unfair convictions since the coup, are testament to the Myanmar courts’ total lack of independence.

My colleagues on the Special Advisory Council for Myanmar were members of the UN fact-finding mission that called in 2018 for the investigation and prosecution of junta leader, senior general Min Aung Hlaing, for genocide, crimes against humanity and war crimes.

The fact-finding mission completed its mandate in 2019 and handed over information to the Independent Investigative Mechanism for Myanmar, or IIMM. Established by the UN Human Rights Council in 2018 on my recommendation, the Mechanism is collecting evidence of the most serious international crimes and violations of international law in Myanmar and preparing files for criminal prosecution. The UK contributed half a million pounds of funding to the IIMM this year to increase its evidence gathering capabilities.

But the Mechanism is not a court or a prosecution service. Without a court with the requisite jurisdiction – and the willingness to use it – the Mechanism will continue collecting evidence indefinitely while Myanmar burns.

The IIMM is cooperating closely with several international justice processes that are already underway, such as the case brought by The Gambia under the Genocide Convention currently before the International Court of Justice. The proceedings are an important step towards justice for the Rohingya but, as the International Court of Justice is tasked with settling disputes between states, will not result in criminal prosecution of those responsible for the atrocities.

That is the role of the International Criminal Court, or ICC. The ICC also has an investigation open into the situation in Myanmar, but it is extremely limited. Myanmar has not signed the Rome statute of the ICC and so the court only has jurisdiction over crimes where part of the criminal conduct took place on the territory of a country that has, such as neighbouring Bangladesh, where there are currently one million Rohingya refugees from Myanmar. In this way, the ICC is able to investigate the crime of deportation, which necessarily has a cross-border element to it. Although another important step towards justice for the Rohingya, under such constraints the investigation cannot deliver accountability for the full extent of the Tatmadaw’s crimes.

This can change. A National Unity Government of Myanmar (NUG) was formed by elected parliamentarians in April to lead Myanmar through the crisis caused by Min Aung Hlaing’s violent attempt to seize power. The NUG lodged a declaration with the ICC in July accepting the court’s jurisdiction in Myanmar dating back to 2002, when the court was established.

For the first time the lead prosecutor of the ICC – the UK’s Karim Khan QC – can investigate the Myanmar military’s persistent crimes against people up and down the country – and the IIMM has two million pieces of evidence to help him do it.

This is the best chance for justice that Myanmar has ever had. As Min Aung Hlaing’s scorched earth campaigns continue to rage, every effort must be made to ensure this chance is not lost.