A massive oil spill in the Baltimore Harbor that began Wednesday has now dumped 5,000 gallons of diesel fuel into the harbor, more than doubling the amount initially reported.

More than 100 personnel have been working around-the-clock to clean up Baltimore Harbor after 2,000 gallons of diesel fuel spilled into the harbor Wednesday after what officials said was an accidental overfill of diesel tanks that supply power for backup generators at Johns Hopkins facilities in East Baltimore.