Christopher suffered a gunshot wound to the stomach outside a nightclub in Toulouse, with the assailant still on the run.
Police were called to the area where the incident took place and investigations have already started to apprehend the culprit.
26-year-old Christopher, who was an amateur footballer and had a trial with Brentford in 2011, was rushed to the hospital but died on arrival.
Serge Aurier was in action for the full 90 minutes as Tottenham Hotspurs defeated Arsenal 2-1 in the North London derby on Sunday but the 27-year-old Ivory Coast international has now been thrown into a state of mourning.
A Tottenham statement read: "The club is deeply saddened to confirm media reports that Serge Aurier's brother passed away in the early hours of this morning.
"We are supporting Serge at this difficult time and we ask that the privacy of the player and his family is respected.
"Everybody at the club sends their sincerest condolences to Serge and his family.
"Our thoughts are with them all."
Aurier has made 39 appearances in all competitions for Jose Mourinho’s men this season.
He joined Tottenham Hotspurs from French champions Paris Saint Germain in the summer of 2017 and was a member of the Ivorian side that won the 2015 Africa Cup of Nations.
