Transcript for 1 Marine dead, at least 2 injured in training disaster
We move to the deadly military training disaster in San Diego. At least one marine dead. Eight missing. Their vehicle taking on water. The Marines based at camp Pendleton. Will Carr has been following this all day. Reporter: Tonight, the military training disaster aboard an amphibious assault vehicle. One marine is dead, two in critical condition. Eight more still missing. Officials in a desperate search and rescue operation. The Marines, based at camp Pendleton, were training off the navy-owned island of San Clemente about 65 miles from San Diego. The exercise taking a catastrophic turn at 5:45 P.M. Thursday. Emergency reports that the armored personnel carrier was taking on water. Rescue crews searching in choppy seas, finding eight people. This vehicle is big. It's almost as big and heavy as a tank. And so when water gets aboard, it sinks very quickly. Reporter: 15 Marines and 1 sailor were inside the vehicle. The military has used them since the 1970s to transport Marines from sea to land. The coast guard and Navy are searching in the waters for the missing crew members. There have been mishaps in these amphibious vehicles over the years, but none like this. Did hatches get opened that shouldn't have been opened and allowed seawater to quickly get in? Was there a mechanical failure? Reporter: As the search continues tonight, the Marines have decided to stop using that vehicle on water until they can figure out exactly what went tragically wrong. Will Carr on that breaking news. Thank you.
This transcript has been automatically generated and may not be 100% accurate.