Kermiche and the other assailant were killed by police.
But the tag was turned off for a few hours every morning, corresponding with the time of the church atrocity.
He then tried to get to the war-ravaged country again by making his way through Switzerland before being detained.
A nun who escaped the attack said she saw the attackers video themselves and “give a sermon in Arabic” around the altar at the church near Rouen in Normandy.
The second time he tried, he got kicked out of Turkey and was sent back to Switzerland where he was arrested at Geneva airport on May 14 previous year.
Responsibility for the attack – the first jihadist attack on a church on French soil by the IS – was claimed via Amaq, the mouthpiece agency of Islamic State, which in recent years has become notorious for its brutality in Syria and Iraq.
A government spokesman said that a bomb disposal unit is checking that there are no hidden explosives in the church and surrounding area.
“The investigations are ongoing. It’s a dramatic situation”.
Update: The priest has been identified as The Rev. Jacques Hamel. “And I invite all non-believers to unite with this cry”, Archbishop Dominique Lebrun wrote, according to the AP. According to the New York Times, this latest incident happened at the church in Saint-Etienne-du-Rouvray when a Mass was underway.
The motivations for the hostage-taking were not yet clear, but the Paris prosecutor’s office said the case was being handled by anti-terrorism prosecutors. I assure you, we will win this war.
“The two killers came out and they were neutralized”, he said.
“An attack against a religious institution and a man of God is an attack against all religions and faith itself”, Dr. Moshe Kantor, president of the European Jewish Congress, said in a statement following the attack. He did, however, add that the French anti-terrorism experts have been called into investigate. “He went to Turkey and security services were alerted after this”.
He had already threatened to attack a church, according to witness testimony collected in his neighbourhood.
“Singapore condemns this terrorist attack in a house of worship”. They attempted to storm the church, but the assailants used three hostages as a “curtain” in front of the door, Paris prosecutor Francois Molins said.
In France, the Normandy attack comes 12 days after a 31-year-old Tunisian killed 84 people in the French Riviera city of Nice when he ploughed his heavy goods truck into a crowd of revellers.
In April 2015, Algerian national Sid Ahmed Ghlam was arrested in Paris on suspicion of planning to attack churches in the capital. He is charged with killing a young woman inside her auto the same day.
French officials later confirmed that the person who died in the attack was an 84-year-old priest. Abaaoud is also the mastermind behind the November 13 Paris attacks, as well as the March 22 Brussels airport attack.