A 16-year-old boy taken into police custody on suspicion of involvement in a terrorist attack that left a priest dead in northern France has been released after authorities determined he was not involved, the Interior Ministry said Wednesday.
The Algerian-born boy, whose older brother was the subject of an arrest warrant for travelling to the Iraq-Syria region under a false identity, should continue to exercise caution, Interior Minister Bernard Cazeneuve told Europe 1 Radio.
"We will know more in the next few hours," Cazeneuve said.
The boy was taken into custody on Tuesday after two self-declared terrorists took hostages in a church in Upper Normandy as Mass was being said and murdered an 86-year-old priest before being killed by police.
One of the two attackers has been identified as Adel Kermiche. The boy's brother - who has not been named as a suspect in the attack - had tried to travel on Kermiche's papers in 2015, but was stopped.
Kermiche, 19, a French citizen, had been under electronic surveillance after also trying to travel to Syria twice.
The identity of the second attacker is still not known, Cazeneuve said.
The Islamic State extremist militia claimed the two attackers as its "soldiers" after the attack.
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French President Francois Hollande said two "terrorists claiming to be followers of Islamic State" entered a church in northern France on Tuesday morning, killing an 84-year-old priest and seriously wounding another person.
French President Francois Hollande said that a hostage-taking Tuesday at a church in Upper Normandy was carried out "by two terrorists claiming to be followers of Islamic State."
An 84-year-old priest was killed Tuesday at a church in northern France where two armed assailants took five hostages and were subsequently killed by police.