A new investigation shows that a cigarette was the cause of the fatal crash on the flight to Egypt.

The report concluded that the pilot of the EgyptAir flight lit a cigarette in the cockpit and caused the oxygen in the plane's emergency mask to burst into flames.

At the time of the crash, smoking was banned in the cockpit, but it wasn't until 6 years later.

No group claimed responsibility for bringing down the plane.

It was claimed that explosives were found on the bodies of the crash victims.

EgyptAir Flight MS804 Wreckage Getty

The plane crashed into the Mediterranean Sea, killing all 66 people on board.

Richard Osman's second daughter was just three weeks old when the crash happened.

Julie Heslouin, who lost her father and brother in the crash, responded to the new report, saying that they have been waiting since 2016 to understand why they lost their loved ones.

There was no mention of oxygen leaks or cigarettes when France's Civil Aviation Accident Bureau claimed it was likely a fire that started in the cockpit.

The victims were mourned at a candle light gathering in Cairo.

The report has been sent to the Court of Appeal in Paris.