Spanish police have released footage of the moment a woman fainted and fell onto the tracks at a Madrid subway station.

The footage showed an off-duty police officer jumping onto the rails to rescue her, pulling her to the opposite side of the tracks as a train approached.

The train stopped when the driver saw people on the platform signalling, and realized something was wrong. The 52-year old woman was attended to by a doctor who was at the station.

Talk about putting your own life in danger to save someone else!