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Admiral Tong is the commanding officer of the Mercury class battlestar Chronos.
Sent to investigate a distress signal near the Armistice Line, Tong's ship is waylaid by Cylon forces. Admiral Rohner orders Helena Cain to investigate the matter.
When Admiral Helena Cain finds Chronos, Pegasus herself is attacked.
Tong and 93 other survivors tried to escape to a tylium fuel depot, where Cylon Centurions ambush and kill everyone except Tong, who is the sole survivor.
Tong becomes psychotic with fear as he believes that the Cylons plan to return to kill everyone. Agitated beyond any help, Tong kills himself in Cain's quarters (Battlestar Galactica: Pegasus).