A dark, viscous liquid seeps through the ocean. 

An oil spill? No, it's molasses—and it has created an environmental catastrophe that so far has killed thousands of fish that dwelled in Honolulu Harbor.

Last week, a pipeline owned by shipping magnate Matson carrying molasses from Hawaii to California leaked as much as 233,000 gallons of molasses into the waters of Honolulu Harbor. The amount is equivalent to more than 5,500 barrels of oil.

Hawaii state officials said there was little they could do to clean up the spill, warning the public to stay out of water in the area. Matson pledged to cover costs associated with the spill response.