Local authorities said on Saturday that five bodies were discovered in the middle-class area of Navarte on the outskirts of Mexico City.

Police found the bodies with their hands tied and some showing apparent signs of torture, said police.

One of the bodies was identified as Ruben Espinosa, a photojournalist for Mexico's investigative reporting magazine "Proceso."

According to Proceso, Espinosa - who also worked for other publications - went into "self-exile" from the eastern state of Veracruz, where he felt threatened.

In January, the Committee to Protect Journalists (CPJ) reported confirmation of four journalists killed for their work since 2011, adding that it was still investigating at least six other deaths.

The bodies were discovered after neighbors alerted the police on Friday night, according to the Mexico City prosecutor's office.

Mexico has experienced a wave of brutal violence linked to drug cartels since 2006, when the government launched a military campaign against organized crime.

Cartel-linked violence has left more than 100,000 dead and 22,000 disappeared, mostly in the country's northern regions near the US border.

Mexico City has witnessed fewer cases of violence linked to the drug trade, in comparison with many other parts of the country.

ls/gsw (AP, AFP, EFE)