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Michael Brown shooting: Protests as police kill armed man

19 August 2014 Last updated at 22:39 BST

The police killing of a second black St Louis-area man in 11 days has threatened to further enflame tensions.

On Tuesday, police officers shot dead a man who brandished a knife at them, St Louis Police Chief Sam Dotson said.

The 9 August police shooting of Michael Brown, 18, has sparked days of violent protests in the town of Ferguson, prompting a heavy police crackdown.

Aleem Maqbool reports from Ferguson.