Officers were called to Victoria Underground Station at 2.45pm yesterday (11 July), after receiving reports that a man had been seriously assaulted.
A 16-year-old boy from Hillingdon and a 15-year-old girl from Croydon were both arrested on suspicion of assault occasioning grievous bodily harm.
They have been released under investigation while enquiries into the incident continue.
A man in his seventies was taken to hospital, though his injuries are not believed to be life threatening or changing.
If anyone witnessed the assault taking place, we urge them to contact BTP by calling 0800 40 50 40 or texting 61016, with the reference 334 of 11 July.