Mysterious foam covers Japanese city after destructive earthquake

A mystery layer of foam covered the streets of a city in Japan in the aftermath of an earthquake which hit the country this week. The foamy substance appeared in the centre of the southern city of Fukuoka in the early hours of Saturday, following a 7-magnitude quake which shook the Kumamoto region. A magnitude-6.5 earthquake had struck the same area on Thursday night, but residents of Fukuoka reported little damage in the aftermath of either. People posted images and a video of the unexplained foam on Twitter, leading many to speculate on its cause, with one theory that a tremor may have caused a underground water pipe to burst.

The disaster left 410,000 homes without water and 200,000 with no power, forcing crowds of people to queue for food and water at emergency aid centres set up in the wake of the aftershocks.
There has been no official explanation for the foam as of yet.