French church attacker tests positive for Covid-19
Brahim Issaoui, 21, remains hospitalised after being shot several times by police following the knife rampage at Nice's Notre-Dame basilica on Thursday.
"He hasn't yet been questioned, his prognosis remains uncertain," another inquiry source told AFP late Monday.
Issaoui, who was known to Tunisian police for violence and drug offences, arrived in France only last month, having first crossed the Mediterranean to the Italian island of Lampedusa.
Four more people were detained for questioning Tuesday morning, including a 29-year-old man suspected of being in contact with Issaoui, a judicial source told AFP.
They were taken into custody in the Val-d'Oise department just north of Paris, which has several suburbs with large immigrant communities.
Six people were previously detained over suspected links with Issaoui, but only one remained in custody Tuesday – a 29-year-old Tunisian who was aboard the boat that brought Issaoui to Lampedusa, sources said.
Italian media reports say Issaoui was initially placed in quarantine with nearly 400 other migrants aboard a ferry boat before being allowed to disembark at Bari in southern Italy on October 9.
Investigators have since determined he arrived in Nice on October 27, just two days before the church attack.
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One woman had her throat cut and a church employee was also fatally stabbed inside the church, while another woman managed to flee but later died of her wounds.
Police say Issaoui yelled "Allahu Akbar" (God is Greater) as they apprehended him, leading officials to say it was the latest in a string of jihadist attacks on French soil in recent years.