Federal investigators have interviewed the captain and other crew members of a scuba diving boat that caught fire and sank off of Southern California, killing 34 people.
Jennifer Homendy of the National Transportation Safety Board says Tuesday that the captain, the boat's owner and others underwent hours of detailed questioning. She won't disclose details.
The captain and four crew members are the only survivors of a pre-dawn Labor Day fire aboard the Conception off the Channel Islands.
Authorities say they were on deck, while those sleeping below were trapped by the quick-moving blaze.
All but one body has been recovered.
Homendy says crew members were given alcohol and drug tests. She says the alcohol tests were negative, and the drug results are pending.
The boat's fire protection systems will also be checked. The Coast Guard says the vessel wasn't required to have sprinklers.
