The head of France's internal intelligence agency had warned the country was being 'clearly targeted' by ISIS a week before the Paris to Cairo flight took off.

EgyptAir Flight MS804 has gone missing over the Mediterranean with 66 people on board amid reports of a merchant ship captain having seen a 'flame in the sky'.

An Egyptian civil aviation authority spokesman has said the plane, with 15 French passengers and one Briton on board - most likely crashed into the sea.

Patrick Calvar (pictured), the head of French internal intelligence, warned last week that ISIS was planning new attacks and France was still their number one target

The cause of the disaster remains unknown but it comes seven months after a bomb blew up a Russian airliner over the Sinai desert, killing all 224 people on board.

ISIS later revealed images of a soda can bomb which they claimed to have used to bring the Metrojet plane down.

It has now emerged that Patrick Calvar, the head of France's DGSI agency, told a parliamentary committee on national defence in Paris on May 10 that ISIS was planning 'a new form of attack'.

France's security forces have remained on high alert since the Paris attacks (pictured) in November, which killed 130 people

The DGSI (General Directorate for Internal Security) is France's equivalent of the MI5 and is responsible for guarding against internal threats

France was targeted twice last year - with the Charlie Hebdo attack in January and the Paris attacks in November - and the French security forces are on a state of high alert.

Mr Calvar was quoted in The Local as saying: 'We risk being confronted with a new form of attack: a terrorist campaign characterised by leaving explosive devices in places where big crowds gather, multiplying this type of action to create a climate of panic.'

He made no mention of attacks on aircraft but said he believed France was 'the country most threatened' by ISIS, which is often known as Daesh, and also warned that Al-Qaeda remained a threat and was champing at the bit to 'restore its image' as a major player, especially in the Maghreb and the Arabian peninsula.

Mr Calvar said while last November's attacks in Paris that killed 130 people were conducted by suicide bombers and jihadists armed with Kalashnikovs, a new form of attack was possible.

We know that Daesh is planning new attacks...and that France is clearly targeted Patrick Calvar

It may be several weeks or even months before it is known what brought down Flight MS804 but Mr Calvar's comments will increase fears of spectators with less than a month to go before the start of the Euro 2016 football tournament in France.

Mr Calvar said: 'We know that Daesh is planning new attacks using fighters in the area, taking routes which facilitate access to our territory and that France is clearly targeted.'

He said ISIS had suffered military setbacks in Syria and Iraq and wanted to take revenge on members of the coalition, including France, which were behind the air strikes on ISIS targets.

Mr Calvar said while last November's attacks in Paris that killed 130 people were conducted by suicide bombers and jihadists armed with Kalashnikovs, a new form of attack was possible.

This is a so-called soda can bomb, published in the ISIS magazine, which they claimed to have used to destroy the Russian airliner in October, killing 224 people