Cairo protester tackles tanks 'like Tiananmen Square'
Egypt's presidency has declared a state of emergency after scores of people were killed when security forces stormed protest camps in Cairo.
The camps had been occupied by supporters of former president Mohammed Morsi, who was deposed in early July.
The BBC's Hugh Sykes in Cairo described a big cloud of black smoke from burning tyres, and barricades of tanks.
He said one young man stood in front of a tank driven by security forces in a scene "like Tiananmen Square" - a reference to the famous image from protests in Beijing in 1989.