The Paris prosecutor's office said on Sunday that a fifth person had died from their wounds following Tuesday's Strasbourg Christmas market shooting.
An official with the prosecutor's office said the victim was a Polish national and gave no other details.
The gunman, Cherif Chekatt, was killed on Thursday night after firing on police, ending a two-day manhunt that involved more than 700 members of the security forces.
ISIS claimed him as one of its soldiers on Thursday, who “carried out the operation in response to calls for targeting citizens of coalition countries” fighting the militant group, according to a statement on its Amaq news website. The group provided no evidence for the claim.
Witnesses had told investigators that the attacker cried out “Allahu Akbar” (God is Greater) as he opened fire on Tuesday on the Christmas market in Strasbourg, a target Paris Prosecutor Remy Heitz suggested may have been chosen for its religious symbolism.
The Strasbourg attack was the latest in a succession of attacks linked to Islamist militancy in France going back to March 2012. Since January 2015 more than 240 people have been killed in various attacks, although the last one had been in May.
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