Malaysia plane: Vessels search for black box pulse signals
6 April 2014 Last updated at 22:48 BST
A Royal Navy ship, HMS Echo, has joined the search in the southern Indian Ocean where electronic signals have been detected in the hunt for the missing Malaysian airliner.
Investigators believe the sounds could be coming from the aircraft's black box flight recorders.
A Chinese vessel has twice detected a pulse and Australia's HMS Ocean Shield is investigating a possible third signal elsewhere in the massive search zone.
Jon Donnison reports from Perth where the search effort is being co-ordinated.