The child almost fell off a fifth-floor balcony, hanging precariously on the edge, unable to move, when a young man saw a crowd around the building while passing by. He climbed up with unbelievable pace, rescuing the small boy from harm, French media BFMTV reported. The incident occurred in the French capital on Saturday.
"I did it because it was a child," Le Parisien newspaper quoted Gassama as saying. "I climbed… Thank God I saved him."
The mayor of Paris, Anne Hidalgo has praised the hero and said she had talked to him on the phone, adding that the city would "support him in his efforts to settle in France."
"This reckless and brave man saved the life of a child at the risk of his own. I wish, like many other Parisians, to congratulate him, the Spiderman of the 18th [district]," the mayor wrote on her Twitter account.
The heroic deed has prompted a debate on social media, with many Twitter users praising the bravery of the migrant.
Some people have also compared the stance of the French authorities and US President Donald Trump, who has been tough on illegal immigration.
According to the BFMTV, President Emmanuel Macron met Gassama in Elysee Palace on Monday in order to thank him personally for his bravery and promised the young man he would be granted French citizenship and a job.