(BBC) — Teams searching for the missing Malaysia Airlines plane are to deploy a robotic submarine for the first time.

Search chief Angus Houston said the Bluefin-21 drone would be sent down as soon as possible to search for wreckage on the sea floor.

Teams have been using a towed pinger locator to listen for signals from the plane’s “black box” flight recorders.

But no new signals have been heard since 8 April, amid concerns the flight recorders’ batteries have expired.

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