Pamplona, City Hall Square

Close to noon, during the 'chupinazo', the crowd celebrates the beginning of San Fermin and the alcohol, euphoria, and heat exude a festive atmosphere.

In one corner of the square

A group of young people heckle and throw glasses towards one of the balconies. At one point, one of the young people tries to climb the facade up to the balcony when he receives a punch in the face from above.

The video has become a viral phenomenon and is probably one of the most memorable moments of the 'Sanfermines 2015' which end today.