Three journalists thought to have been kidnapped in Mexico have been freed according to national reports, while one remains missing.

Journalism.co.uk reported on industry calls for the safe release of four journalists who went missing on Monday after covering a demonstration taking place outside a prison.

Police have now reportedly announced that two cameramen, Javier Canales and Alejandro Hernandez, were freed over the weekend while another journalist, Hector Gordoa, was freed on Friday. It remains unclear whether the three men were released by their captors or rescued by security forces.

Reporters Without Borders said the country is one of the deadliest in the world for journalists.

We are very relieved to learn to learn that cameramen Jaime Canales of TV Milenio and Alejandro Hernández of Televisa have been freed and our thoughts are with reporter Oscar Solís of El Vespertino, who is still being held. The war between the drug cartels and the authorities is wreaking havoc in Mexico and journalists are being targeted with increasing frequency. Those responsible for killing journalists take advantage of the prevailing impunity, which is fuelling the violence.

A total of 67 journalists have been killed in Mexico since 2000 and 11 have gone missing since 2003. In the 2009 Reporters Without Borders press freedom index, Mexico was ranked 137th out of 175 countries.