A fifth person has died as a result of Tuesday's terror attack in Strasbourg. The victim, 35-year-old Barto Pedro Orent-Niedzielski, died after five days in a coma.

"My brother Barto Pedro Orent-Niedzielski has just passed away. He thanks you for the love and strength you have given him," the brother of the 36-year-old Polish-born victim wrote on Facebook.

Cherif Chekatt, who was on a French list of possible extremist security risks, attacked a Christmas market in Strasbourg on Tuesday night, and was shot dead by police on Thursday.

It came after residents of the eastern French city of Strasbourg filled a city square Sunday for a memorial to the people shot dead and the dozen wounded by a gunman at their Christmas market.

The hour-long ceremony took place in Kleber Square by the city's Christmas market, near where the gunman opened fire on Tuesday evening.

According to the local newspaper DNA, more than 1,000 people attended the memorial, which ended with a minute of applause and a rendition of France's national anthem, "La Marseillaise."