Nineteen Somali pirates took over the boat 'The Quest' last Friday, 100 miles off Oman, killing Americans Jean and Scott Adam and Phyllis Macay and Bob Riggle early this morning.

Read the tragic  story after the bump.

Four Americans taken hostage by Somali pirates off East Africa were shot and killed by their captors Tuesday, the U.S. military said, marking the first time U.S. citizens have been killed in a wave of pirate attacks plaguing the Gulf of Aden and the Indian Ocean for years.

U.S. naval forces who were trailing the Americans' captured yacht with four warships quickly boarded the vessel after hearing the gunfire. They tried to provide lifesaving care to the Americans, but they died of their wounds, U.S. Central Command in Tampa, Florida said in a statement.

A member of a U.S. special operations force killed one of the pirates with a knife as he went inside of the yacht, said Vice Adm. Mark Fox, commander of U.S. naval forces for the Central Command.