"It can be thrown over the wall, it can be brought in by visitors - secreted in their bodily orifices - or in children's nappies… staff corruption is an issue in many prisons," he added.

Others, meanwhile, were recovered by the police dumped on the side of the road or "thrown over" the site's gate, Mr Huggins said.

He was sitting with Zahraa and the boys, a few hours after the strikes resumed, on the street by their makeshift tent, which was really just two rugs thrown over an improvised frame.

Before the bout, the 31-year-old from Derby was had red paint thrown over her as she made her way from her hotel to The Theater inside Madison Square Garden.

She is in a Nine Inch Nails 2008 tour T-shirt, thrown over a slip dress with fishnets on, and Cortez is in a T-shirt, cargo shorts and boots.