Smelly Foam Oozing From Chinese Street Leaves Commuters Baffled (PHOTO)

Chinese commuters got a shocking surprise earlier this week when gallons of putrid foam started oozing out of the street.

The photo was reportedly taken in the city of Nanjing around 9 p.m. on Monday and the substance covered an area of "forty or fifty square meters," according to a translation of news outlet Longhoo. Firefighters and police quickly cordoned off the area and washed the foam away.

Uploaded by user alongyourfuselage.

Officials say the only explanation so far is that it could be the byproduct of subway construction in the area. But an in-the-know reddit user who said they used to work for a medical device company said the substance looks "identical" to the byproduct of blood and concentrated hydrogen peroxide.

Either way, ew.

A similarly shocking photo was posted to reddit last month that showed a fluorescent green substance flowing from a pipe into a waterway.