Fresh analysis from Channel 4 News of police video taken during the Marikana massacre sparks nationwide debate in South Africa. Inigo Gilmore returns to the scene to hear from key witnesses.

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Warning: some viewers may find the images in this film distressing from the outset

As we scrolled through the police video footage we were astonished by what we found, writes Inigo Gilmore. In among the shaky images we came across a distressing scene where a police officer calls for restraint, shouting 'don't shoot, don't shoot him' just moments before gunfire rings out. In the next scene a body of miner appears lying motionless on the ground.

As the camera shakily pans back and forth one of the officers, standing next to the body, can be heard boasting about how he took the young man down. Chillingly the unidentified officer, can be just be made out saying: "M*********r, I shot him at least 10 times."

The body of the young man has been identified as 26-year-old Thobile Mpumza. He was shot 12 times.

British journalist Inigo Gilmore combed through the extensive footage submitted to the Commission, and found the extraordinary video. South Africa's The Daily Maverick

This scene is just one of several disturbing moments captured by two policemen on August 12th 2012 in Marikana when 34 miners died, shot by police guns.

Images of an initial shooting were captured by news agencies and were beamed around the world. They were shocking and came to define the Marikana massacre. Police have always maintained that they were acting in self defence that day after coming under attack from protesting miners bearing arms.

But this footage gives a very different picture of what happened and raises many important questions. It directly challenges the police's own narrative. The police officers filmed this video in an area of scrubland and rocks where most of the miners actually died that day.

Since my report about the police footage aired on Channel 4 News on Sunday, it has triggered a storm in South Africa and has been seized on by those who have accused police of murdering defenceless miners.

Watch: Police shooting video footage

Critically it has raised a significant challenge for the judicial commission of inquiry, set up by Jacob Zuma's government following a national outcry over the killings. It is possibly the most important evidence submitted so far - but until we highlighted its contents and pointed out the implications of the video, it had almost been almost overlooked.

On Tuesday morning (29th January) the Commission went into emergency session to discuss the issues raised by the Channel 4 News report. Afterwards, Judge Ian Farlam, said: "In the circumstances, the commission is of the view that it is premature to draw conclusions from the video footage that is included in the broadcast."

Judge Farlam confirmed that two policemen, Captain Rylands and Sergeant Mahlatsi, filmed the footage and that the commission had seen it.

I came across this video when I was in South Africa filming a follow up report to the Marikana massacre. In that report - aired today (see video above) - I spoke to three miners who allege further police brutality - this time in the run up to their planned testimony at the commission. They told me that police were harassing, beating and torturing miners, themselves included, in a bid to stop them telling what they had seen that day.

One of those I interviewed was Shadrack Mutshamba who in September last year gave shocking details of what happened on the day of the massacre. He says that on August 16th 2012 he witnessed how police shot miners even as they tried to surrender. Some, he says, were hit with bullets to the head fired by policemen a short distance away.

Watch: I saw police murdering strikers claims South African miner

Shadrack, who is now increasingly alarmed about the ongoing intimidation of miners wanting to testify at the commission, claims that those incidents took place in the same area where the police footage was filmed, in among the rocks at the 'Killing Koppie'. The police video appears to tally closely with the description Mtshamba painted for me back in September last year.

Greg Marinovich, a veteran South African journalist, writing in The Daily Maverick under a headline "Truth and Lies" said that the Channel 4 News report and analysis of the police video had opened a path to understanding what happened that day.

He wrote: "We are discussing the footage here, now, because of a piece that appeared on Channel 4 in the UK. British journalist Inigo Gilmore combed through the extensive footage submitted to the Commission, and found the extraordinary video."

Referring to the area known as Small Koppie,or the "Killing koppie", where police put yellow paint markings after the massacre, Marinonvich writes: "The footage shows several of the bodies lying exactly where later crime scene letters would mark the scene...There has, for some time now, been no doubt, even for those most likely to believe the tale put out by the police, that it was indeed mass murder that occurred at Small Koppie - but yellow paint on rock does not quite bring home the horror like an amateur video shot by a policeman on the scene does."

The storm over our report has put further pressure on the police who have already been accused by families of the victims of hiding or destroying other video evidence. The police video that was submitted to the commission appears to have been heavily edited and the possibility that other video evidence could be out there raises some critical issues for those running the inquiry.

Our report has stirred much soul searching and public anger in South Africa where it has become headline news. The reaction has underlined just how far the commission has to go if it is to gain public trust - and find out what really happened that day.

Follow Inigo Gilmore on Twitter @inigogilmore

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