A French ISIS fanatic who ended up murdering a Catholic priest got through a police investigation to become an airport baggage handler ‘easily’, it emerged today.

Abdelmalik Petitjean and Adel Kermiche, both 19, were both on terrorist watchlists when they slit Father Jacques Hamel’s throat in Normandy on Tuesday.

Now it has emerged that Petitjean worked full time at Chambery airport, which is used by more than 250,000 passengers a year including many from Britain, until just three months ago.

It comes as ISIS released a new video of the teenager calling on fellow extremists to 'destroy' France and launch attacks on its allies.

Abdelmalik Petitjean worked full time at Chambery airport, which is used by more than 250,000 passengers a year including many from Britain, until just three months ago

It comes as ISIS released a new video of Kermiche's accomplice calling on fellow extremists to 'destroy' France and launch attacks on its allies

Dressed in a striped t-shirt, Petitjean speaks mostly in French but uses some Arabic phrases, and appears to be filming in a home.

Addressing President Francois Hollande and Prime Minister Manuel Valls directly, he says: 'You will suffer what our brothers and sisters are suffering. We are going to destroy your country.'

'Brothers go out with a knife, whatever is needed, attack them, kill them en masse.'

Meanwhile, a Syrian refugee staying at a French centre for asylum seekers was this morning taken in for questioning in connection with a deadly jihadist attack on a church, a source revealed. A photocopy of his passport was found at Kermiche's home.

The arrest, which took place in central France yesteday, raises to three the number of people currently being held as part of the investigation into Tuesday's murder. A cousin of Petitjean and a minor arrested just after the attack were being questioned along with the Syrian.

Last night it emerged that Petitjean started as a porter at Chambery Airport in December after completing his Baccalaureate at the Marlioz high school in nearby Aix-les-Bains, where he lived.

There have been numerous security scares at French airports over the years, and all employers are now meant to undergo stringent tests.

‘Petitjean had no trouble getting through a police investigation and psychological evaluation,’ said a source close to the ongoing investigation into his crimes.

‘He was considered to be a hardworking, friendly young man who did not pose any danger to passengers or others using the airport. He got through the police investigation easily. ’

Petitjean left the airport in April, and in June was caught by Turkish intelligence services as he tried to get into the Isis caliphate in Syria.

Last Friday there was a warning that Petitjean was back in France and ready to strike, but by this time it was too late for police in his homeland to catch him before he milled Father Jacques.

Abdelmalik Petitjean and Adel Kermiche, both 19, were both on terrorist watchlists when they slit Father Jacques Hamel’s throat in Normandy on Tuesday

Petitjean and Kermiche butchered 86-year-old priest Jacques Hamel (pictured) at a church in Normandy

This morning a second video showing Petitjean calling for more attacks on France was released by ISIS.

It came a day after another one was circulated in which Petitjean and Kermiche, who was electronically tagged since last March, swear allegiance to the terrorist organisation.

French prime minister Manuel Valls, who is facing calls to resign, today said the antiterrorism judges who let Kermiche out of prison in March with the tag should not be blamed for ‘an act of terrorism’.

They have to take a ‘different, case-by-case, approach,’ he said, while admitting that the decision to free Kermiche under such weak bail conditions was ‘a failure’.

Mr Valls also said he was ‘open’ to the idea of stopping foreign financing for the building of mosques in France.

There are some five million Muslims in France – the largest group of its kind in any western European country – and they frequently complain about the lack of places of worship available for them.

Mr Valls, who has often been criticised for his reactionary domestic policies, told Le Monde that his secular country needed ‘to invent a new relationship with Islam’.