Egypt Air flight MS804 disappeared off the radar in the late hours of Wednesday night or very early hours of Thursday morning.
The plane, an Airbus A320, carrying 66 people was en route from Paris to Cairo and over the Mediterranean Sea when it "vanished"; two infants, a child and one Briton are among the missing. The passengers however were multi-national.
Contact with radar was lost above the Mediterranean Sea at about 175 miles, or 280km, from the Egyptian seacoast.
Ten crew members were on board, three of whom were security personnel. That according to the French Transport Minister is usual practice.
Relatives of those missing are gathering at the Charles de Gaulle airport in France and at Cairo International airport, Egypt, as they wait any news.
The Guardian reports "The Egyptian aviation ministry has announced a press conference due to take place at 1.30pm local time (11.30am GMT)
There has been some confusion and speculation about what happened to MS804 which has been described in some cases as misinformation.
The Egyptian military have refuted claims of a distress call.
EASA the European Aviation Safety Agency tweeted 30 minutes ago "Aware of the media reports concerning Egypt Air flight #MS804. No further Information at this stage. Following the developments very closely".
News sources are avoiding speculation at this time.
Friday there are reports that oil, plane wreckage and body parts have been spotted as the search continues.