The French vessel Laplace has picked up signals from downed EgyptAir flight MS804’s black boxes, Egypt’s Civil Aviation Ministry announced Wednesday. 

“Black boxes” are the crucial components of any aircraft which record the plane’s movements and technical settings at any given time in the Flight Data Recorder, as well as audio from the cockpit in the Cockpit Voice Recorder. 

Pings from both boxes sound for 30 days after a crash and could be heard from deep underwater.

The Airbus A320 carrying 56 passengers and 10 crew and security officers disappeared last week over the Mediterranean as it flew from Paris to Cairo. It was flying at 37,000ft when it disappeared from the radar at 2:29 a.m.

However, Egyptian authorities revealed the plane emitted emergency signals some two hours later. At around the same time, sailors in a ship in the Mediterranean claimed they saw a massive fireball streaking through the sky.

Egypt’s civil aviation authority confirmed a mid-air explosion had occurred, and after initially saying they weren’t ruling any causes out admitted that a terrorist attack was more likely the cause than a technical failure.

International air and naval teams discovered debris of the plane less than two days later, 180 miles (290 kilometers) north of Alexandria. Among the wreckage: personal belongings of passengers and crew – as well as human remains. A Cairo team is currently carrying out DNA tests on the remains to determine if they belong to those aboard, CBC reports. 

Egypt deployed a submarine to look for the black boxes Sunday. Egypt and France, which are both financing the search, had signed contracts with two French companies specializing in deep-water searches, AFP reports – Alseamar and Deep Ocean Search (DOS). 

Laplace, part of the Alseamar team, carries DETECTOR-6000 acoustic detection systems – designed to detect pings 4,000-5,000 meters below sea level.