A fearless man has been hailed a hero after risking his life by scaling a Paris building to save a four-year-old boy dangling from a balcony. The man identified as Mamoudou Gassama climbed four storeys in just seconds to reach the child at French capital, Paris.

When asked why he took such a risk to save the boy, Mali-born Gassama told Le Parisien: “I did it because it’s a child.”

He then shimmied across the ledge and hoists the child to safety in view of shocked onlookers below.

A man on the adjoining balcony was seen trying to help but could not grab him because of the fence that separated them, Le Parisien reported.

The child is reported to have slipped off the balcony while his father left the apartment to go shopping.

Firefighters tended to both the hero and the boy, both of whom were thought to be in shock.

The so-called Spiderman of Paris suffered only a few scratches in the daring rescue while the child lost a fingernail.

Authorities are understood to have opened an investigation into the incident with local reports arguing the boy would not been in danger if his parents had been at home.