Officials say the hunt for the Malaysian airliner has been set back when two of the three search ships sustaining damage to vital equipment.

The Australian Transport Safety Bureau, which is coordinating the search for Malaysia Airlines Flight 370, said Wednesday that a piece of underwater communications equipment fitted to the Havila Harmony had become tangled in fishing net and had been bent.

The damage was discovered by divers last week during a maintenance visit to the Australian west coast city of Perth. The equipment is scheduled to be replaced by Thursday when the ship will leave Perth to return to the southern Indian Ocean.

The search of the seabed where the Boeing 777 is thought to have crashed had already been disrupted when another ship lost its sonar equipment.