The attackers who stormed a Catholic church in France forced one of the congregants to take pictures and video showing the body of the murdered priest to memorialize the atrocity, a hostage revealed on Wednesday.

The attackers, linked to the Islamic State terror group, took hostages at the church in Saint-Etienne-du-Rouvray, in France's northwest region, during morning Mass. After Rev. Jacques Hamel, 85, was killed, both attackers were killed by police outside the church. The exact timeline of the attack is still unclear.

One attacker was identified as 19-year-old Adel Kermiche, who investigators said tried to travel to Syria twice last year using family members' identity documents. He was detained outside France, sent home and ordered to wear a tracking bracelet.

Under his bail conditions, he could turn off the bracelet for four hours each morning -- a period that matched the time of the attack, according to investigators.

The two attackers had knives and fake explosives -- one a phony suicide belt covered in tin foil, prosecutor Francois Molins said.

An 86-year-old woman, one of five held hostage, said the attackers had handed her husband Guy a cellphone and demanded that he take photos or video of the priest after he was killed. Her husband was in turn slashed in four places by the attackers and is now hospitalized with serious injuries.

[The priest] "fell down looking upwards, toward us," said Jeanine, the ex-hostage. "The terrorists held me with a revolver at my neck," she said, adding it was not clear to her now whether the weapon was real or fake.

 

Jeanine told RMC radio that her husband played dead to stay alive. Two nuns were held hostage along with the couple and the priest, while a third nun escaped and gave the alert.

The identity of the second attacker has not been made public. Police combing the area after the attack detained a 16-year-old who Molins said was the younger brother of a young man who traveled to ISIS territory in the Middle East carrying the ID of Kermiche.

France was still coming to grips with the Bastille Day attack in Nicethat killed 84 people when the church was attacked Tuesday. With the attack threat ranked extremely high, France must also protect 56 remaining summer events, Interior Minister Bernard Cazeneuve noted Wednesday, adding that where "optimal" security cannot be assured, an event will be canceled.

Defense Minister Jean-Yves Le Drian said 4,000 members of the military force called Sentinel will patrol Paris, while 6,000 will patrol in the provinces. They are bolstered by tens of thousands of police and reservists being called up.

Hollande, meanwhile, presided over a defense council and cabinet meeting Wednesday in Paris after speaking with Roman Catholic, Orthodox, Muslim and Jewish leaders.

The archbishop of Paris, Cardinal Andre Vingt-Trois, called on Catholics to "overcome hatred that comes in their heart" and not to "enter the game" of the Islamic State group that "wants to set children of the same family upon each other."

The rector of the main Paris mosque, Dalil Boubakeur, said France's Muslims must push for better training of Muslim clerics and urged that reforming French Muslim institutions be put on the agenda. He did not elaborate.

Young and old in the Normandy town were stunned by the attack.

An 18-year-old neighbor said he had seen Kermiche just three days earlier in nearby Rouen wearing a long Islamic robe.

When he heard about the attack, "I knew it was him, I was sure," the young man told The Associated Press, identifying himself as Redwan. Kermiche had told him and other youth about his efforts to get to Syria and "he was saying we should go there and fight for our brothers."

"We were saying that is not good and he was replying that France is the land of unbelievers," Redwan said. Candles were set out in front of the town hall as residents called for unity.

"It's going to be hard to admit it ... we are scared ...," said Mulas Arbanu. "Be we Christians, Muslims, anything, we have to be together."

Said Aid Lahcen had met the slain priest in the past.

"From the moment when you touch a religion, you attack the nation, and you attack a people. We must not get into divergences, but stay united people as we were before," he said.

The Associated Press contributed to this report.