A towed pinger locator has been reportedly deployed to locate the black box of the missing Malaysia Airlines flight MH370.
In order to retrieve the data recorder, two ships with locator capabilities are searching a 240km (150 mile) underwater path.
Angus Houston, head of the Joint Agencies Coordination Centre (JACC) leading the search, said that two ships had commenced the sub-surface search for emissions from the black box pinger, the BBC reported.
Australia's search chief said it was a race against time as the battery-powered signal fades after 30 days
The former military chief, who is now coordinating the eight-nation search, said it was getting pretty close to the time when it might expire.
The Malaysia Airline plane that went missing on 8 March en route from Kuala Lumpur to Beijing is believed to have crashed in the southern Indian Ocean.
However, no confirmed debris has been found from the plane yet.