Greenpeace blimp floats across Elliott Bay during Sanders rally

A mysterious Greenpeace blimp was spotted Friday floating across Elliott Bay.

"Say no to fossil Fuel $$$," reads the blimp.

The aircraft featured a picture of Democratic presidential candidate Hillary Clinton.

The blimp was airborne during Bernie Sander's rally at Safeco Field.

It in unknown who the owner of the blimp is -- or when it will be taken down.

Cox Media Group