CCTV footage of build-up to Missouri shooting

St Louis County Police said the man, named locally as 18-year-old Antonio Martin, was shot after he pointed a gun at officers at the Mobil station in Berkeley - approximately two miles from where Michael Brown was shot dead in August.

The footage of the build-up to the incident, which took place in the early hours of Wednesday morning, was uploaded to a YouTube channel linked to the St Louis County police department.

It does not appear to show the shooting itself, but some commentators have suggested that you can see the deceased raise his arm towards the officers right at the end of the video - but this is not exactly conclusive proof of what happened.

Police say they will release more details as the investigation unfolds.

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