Page "Vespasian" Paragraph 13

While under the emperor's patronage, Josephus wrote that after the Roman Legio X Fretensis, accompanied by Vespasian, destroyed Jericho on 21 June 68, Vespasian took a group of Jews who could not swim ( possibly Essenes from Qumran ), fettered them, and threw them into the Dead Sea to test the sea's legendary buoyancy.

Indeed, the victims bobbed up to the surface after being thrown in the water from the boats.