MIAMI -- Nearly five years after the deadly boiler explosion onboard the historic SS Norway, a Norwegian cruise line has pleaded guilty to charges of gross negligence.

According to court documents filed Friday, Norwegian Cruise Line Limited was charged with grossly negligent operation of a vessel in a May 2003 ship explosion in Miami.

The explosion killed eight crewmembers and seriously injured 10 others.

Norwegian is liable for at least $500,000 in criminal penalties for the deadliest accident on a U.S.-based ocean liner in more than a decade. The company has also agreed to carry out safety inspections of its vessels with an independent consultant.

The explosion sent debris and a blast of steam through parts of the ship after it docked at the Port of Miami-Dade.

It was not clear why authorities waited five years to file the charge.

The ship was towed to Germany after the blast and has retired from the company's fleet.