Woman, 63, brutally punched to ground by complete stranger

This is the moment a complete stranger brutally punched a woman to the ground before casually walking away.

Footage shows the 63-year-old woman unlocking her bike from beside a road in Argentina as a man walks up behind her.

In a seemingly unprovoked attack, the male then smashes his fist into the back of her head, sending her - and her bike - flying to the ground.

As the woman sits on the floor holding the side of her head, the man continues walking along the street as if nothing has happened.{{file|t=zvFm_1520890105}}