War crimes allegedly carried out by the British military may for the first time be investigated by the International Criminal Court (ICC).
Killings of civilians in Afghanistan and Iraq have been covered up by the state, a BBC news programme will report on Monday.
The United Kingdom's Ministry of Defence denied the allegations.
But children were killed, civilians tortured, and British troops were complicit with evidence reportedly contained in a series of leaked documents sourced from within the Iraq Historic Allegations Team (IHAT).
That team, and Operation Northmoor - which investigated war crime allegations in Afghanistan - were shut down by the UK government in 2017 after Phil Shiner, a solicitor who had taken more than 1,000 cases to IHAT, was struck off from practising law amid allegations he paid people in Iraq to find clients.
But some former investigators said Shiner's actions were used as an excuse to close down the inquiries.
No case investigated by IHAT or Operation Northmoor has led to a prosecution.
The ICC said it has taken the accusations "very seriously", according to the BBC, whose Panorama: War Crimes Scandal Exposed will be broadcast at 21:00 GMT on Monday.
"The ICC said it would independently assess the BBC's findings and would begin a landmark case if it believed the government was shielding soldiers from prosecution," the corporation reported on Monday morning.
The ICC previously concluded it was credible that British troops committed war crimes in Iraq related to the mistreatment of detainees.
The year-long investigation claims to have found evidence of murders by a soldier of the special forces SAS, as well as deaths in custody, beatings, torture and sexual abuse of detainees by members of the Black Watch.
A senior SAS commander was also referred to prosecutors for attempting to pervert the course of justice, the investigation found.
When allegations of abuses by troops first emerged in the years after the invasion of Iraq, the outrage was palpable. In 2006, a video was published of abuse being carried out two years before - British soldiers grabbing four Iraqi boys off the street and dragging them away for a beating, goaded by the soldier filming.
In the southern city of Basra, the video sparked mass protests with the burning of Union flags. Back home, there were calls for soldiers' prosecution, but a year later the case was dropped by prosecutors as the statute of limitations expired.
But after similar stories began to emerge in subsequent years, the media outrage shifted to focus on the prosecutions instead of the abuses. Investigations into soldiers' actions were deemed "witch-hunts" by influential right-wing tabloid newspapers. Former Prime Minister Theresa May blasted "activist, left-wing human rights lawyers" for causing distress to serving and former military personnel.
When IHAT, set up under a Labour government, was shut down by a Conservative government, only 20 cases were taken forward. The other 3,400 on IHAT's books were shelved indefinitely.
Al Jazeera and news agencies