A man has been jailed for four years for knocking a 16-year-old girl unconscious in a street in east London.
Michael Ayoade, 34, of Green Gate Street, Plaistow, pleaded guilty to assault occasioning actual bodily harm on the girl in Plaistow on 13 November.
He also admitted punching a female student unconscious in Newham.
The 16-year-old sustained bruising, cuts to her head and face, and chipped teeth when she was hit on the head near the Black Lion pub.
Ayoade was caught on CCTV staging the random assaults.
The 16-year-old victim was walking near the Black Lion pub in High Street, Plaistow, when Ayoade jogged up behind her and punched her in the head.
She fell to the ground and was left lying unconscious on the pavement.
He attacked university student Daniella Montieth at Plaistow station on 20 November 2011.
He hit the student, who was only 5ft 4in (1.63m), in the side of the head, leaving her sprawled unconscious in the ticket hall.
Judge Roger Chapple said these were "vicious, unprovoked attacks on young, lone females".
"The footage captures graphically the shocking violence of these attacks," he added.
"In both cases the force of the blow was such as to render the victims unconscious albeit mercifully not for long."
Ayoade had previously admitted two counts of assault occasioning actual bodily harm, and one count of possession of cannabis after a bag of the drug was found at his home.
Following the sentencing, investigating officer Det Con Glenn Peach said: "These were unprovoked and cowardly attacks on defenceless women for no reason whatsoever.
"Ayoade has expressed little remorse for what he has done.
"He was a clearly a danger to the public and needed to be caught before he caused serious injury to someone else."