"There is a river of chocolate blocking/flowing in the westbound lanes of I-40 at milepost 211, east of Flagstaff," the Arizona Department of Public Safety tweeted.

A tanker hauling 40,000 pounds of liquid chocolate rolled over on the interstate near Flagstaff, Arizona, yesterday

The tanker was hauling 40,000 pounds (about 3,500 gallons) of 120 degree liquid chocolate, according to the bill of lading the DPS reviewed.

"A latch that connects the main truck with the trailer detached, causing the tanker to roll over," Bart Graves, Arizona DPS Media Relations Specialist, told CNN via email.

"The tanker was heavily damaged in the rear so we had (to) pump out the liquid into the median so the tanker could be lifted onto a tow truck," said Graves.

The liquid is biodegradable and the driver wasn't cited for the accident, according to DPS.

https://twitter.com/Arizona_DPS/status/1084897397447118848/photo/1
https://www.cnn.com/2019/01/14/us/chocolate-spill-interstate-arizona-trnd/index.html