Chunks of black tar have washed up on the shores of Japan, and officials fear they're coming from an Iranian oil tanker that sank last month.
The tanker collided with a freighter off the coast of China in early January. The tanker, which was carrying 136,000 metric tons of oil, then caught fire.
When the ship went down, oil started spreading — fast. Experts feared it could endanger wildlife and marine ecosystems.
Now, Japanese authorities told Reuters they're checking to see if the clumps of oil are in fact from the sunken Iranian tanker.
Additional reporting from Newsy affiliate CNN.
