The Coast Guard responded to an apparent diesel fuel spill in the Ala Wai small boat harbor Monday morning.
The Coast Guard was notified of the spill at about 6:30 a.m.
The sheen is believe to be diesel fuel or some other petroleum product, Coast Guard officials said, adding that the spill area is roughly 200 feet by 30 feet.
The Coast Guard did not have an estimate of the spill amount nor the source of the pollution.
Pacific Environmental Corp. has been contracted to clean up the spill.