Firefighters rescued some ducklings who were trapped behind a metal grille on Rainville Road in Hammersmith and reunited them with their mother.
The ducklings had fallen from a roof of a building into an underground car park along the river front and became trapped behind a metal grille inside the ventilation system.
Firefighter Malena Orlando, who was at the scene said: "We were called to assist the RSPCA with some ducklings that were trapped behind a wall. We arrived and were told that some ducklings had fallen from a roof into the car park ventilation system and were trapped in two separate parts of the void.
"We pitched a short extension ladder to either side of the large ventilation grilles and using an electric cutter and saw, we removed the two sections of the grilles to gain access.
"I then climbed inside the void, catching the ducklings by the hand and placing them into a box. The chicks were then reunited with their mother and after being checked over they swam away down the river.
“We love animals and are always happy to assist if our specialist equipment is required, as in this case. We would always encourage people to call the RSPCA in the first instance if they see an animal stuck or in distress."
The Brigade was called at 1145 and the incident was over for firefighters by 1252. Fire crews from Paddington fire station attended the scene.