Horrified onlookers watched as the helicopter hit the crane amid low cloud and fog near Vauxhall station, south of the river and not far from landmarks such as the London Eye and the Houses of Parliament, and came plunging to the ground.

CNN: London helicopter crash prompts safety questions

It reappeared shortly afterward, on the opposite side of the city, popping out from behind a cloud, bathing Harlem and the East River in a chalky light, and, as though caught by a gust of wind, it rolled toward the Bronx.

NEWYORKER: The Daughters of the Moon

It's estimated the red cloud of heavy metals is now affecting a 30km (19-mile) stretch of the River Danube.

BBC: Toxic sludge carpets homes in Hungary