Towfish 'lost' during search for MH370

A tethered sonar vehicle scouring the ocean floor for missing flight MH370 has been lost after the towfish crashed into a 2200-metre mud volcano.

The towfish and 4500 metres of cable became separated from the vessel and are now resting on the sea floor, the Joint Agency Coordination Centre said in a statement on Monday.

No injuries to crew were sustained on the Fugro Discovery, and it is believed the towfish can be recovered later.

Fugro Discovery is returning to Fremantle where a replacement cable will be installed on the vessel, while the spare towfish on board will be readied for future searches.

The Boeing 777 went missing in March 2014 with 239 people on board.