A British board of enquiry quickly investigated the cause of "Hood"s explosion and produced a report. After criticism that the initial enquiry did not record all the available evidence, a second board of enquiry more extensively investigated "Hood"s loss, and examined the vulnerabilities of other large British warships still in service in light of the probable causes of the explosion. It, like the first enquiry, concluded that a shell from "Bismarck" caused the explosion of "Hood"s aft ammunition magazines. This led to refitting some older British warships with increased protection for their ammunition magazines and some other related improvements.