According to the radio station France Bleu for the Paris region, the Defender of Rights office has opened an inquiry into the incident, which was first recorded in November and involved an ad that was carried by a real estate agency in Lilas in the north western suburbs of Paris.
The agency, an outlet of the nationwide Laforêt real estate company, has apoligized and said it was an isolated incident that should never have happened.
The head of the agency, Laruent Balestra, told France Info that the information contained in the ad had been given by the owner of the property to an employee at the agency and that the employee no longer works for the agency. He also said the agency no longer represents the property owner in question.
He added that it was the property owner who had penned the ad and that the employee that dealt with the ad had taken the ad without knowing what it contained.
The ad was seen by someone who was interested in the apartment and who shared in on Twitter in November.
Just after Christmas, he tweeted it again, this time including the the twitter handle of a number of media workers who followed up on the story.
The rights organization SOS Racism is also believed to be considering taking action over the ad.