Thousands of students have marched through downtown Mexico City to protest against violence.

They carried placards with slogans such as “Being a student in Mexico is more dangerous than being a criminal” in reference to an attack on students at the National Autonomous University earlier this month.

It also referred to the 2014 kidnapping and disappearance of 43 students. Nobody has been convicted for those crimes.

Mexico Student ProtestThousands of students took part in the march (Marco Ugarte/AP)

Thursday’s march came on the 50th anniversary of the 1968 student protest known as the “March of Silence”, when demonstrators marched quietly to contradict accusations that they were unruly.

Weeks later on October 2 1968, troops fired on protesters at Tlatelolco Plaza, killing as many as 300.

Many in Thursday’s march covered their mouths with tape to commemorate the 1968 march.