Passengers travelled on the subway in Mexico City discovered something rather unusual – a seat with a male chest and penis, with a sign allocating the seat "for men only".

The seat features in a video in which a number of commuters look shocked – and appalled – as they try to sit down before spotting the bizarre seat.

A sign on the floor below reads: "It is annoying to travel this way, but not compared to the sexual violence women suffer in their daily commutes."

The campaign, called "No Es De Hombres", was launched by the United Nations and Mexico City authorities to crack down on gender-based violence.

The video highlights that nine out of 10 women in Mexico City have experienced sexual violence "in their daily transfers".

It is one of several campaigns to raise awareness of the issue. In another video, male passengers waiting at a station can see imagines of their behinds on screens opposite.

Although unusual, the campaign has been praised for attracting the attention of passengers to the problem of harassment, sexual violence and women's rights.

Nearly 44% of women in Mexico have been victims of sexual violence at least once in their lives, according to a UN report from 2010.