ALPHONSE ISLAND, Seychelles (AP) — A British-led marine scientific mission off the Seychelles has succeeded in retrieving a key underwater drone from the sea bed, where it had fallen after its cable was cut two days ago.

The camera-carrying drone is a vital piece of equipment for the Nekton Mission scientists as they explore the Indian Ocean depths. Two recovery attempts on Wednesday failed.

Pilot Jimmy Boesen called Thursday's success a welcome relief after two sleepless nights.

He says that "the mission is 50 percent not done if we didn't get it done. So it's a good one."

The Associated Press is the only news agency working with British scientists from the Nekton research team on its deep-sea mission. AP video coverage will include the search for submerged mountain ranges and previously undiscovered marine life, a behind-the-scenes look at life on board and aerial footage.

The seven-week expedition is expected to run until April 19.