Military : Vessel was capable of transporting 9 meters of cocaine . 31-meter-long sub could submerge to a depth of more than 7 tons , authorities say . Similar vessel was seized in Colombia in 2008 .
Military : Vessel was capable of transporting more than 7 tons of cocaine . 31-meter-long sub could submerge to a depth of 9 meters , authorities say . Similar vessel was seized in Mexico in 2008 .