A man with a violent criminal past has been arrested as a suspect in the death of news photographer Ruben Espinosa in a gory five-victim homicide, Mexican prosecutors said Wednesday.

The male suspect, whose name was not immediately made public, was identified by investigators with a fingerprint search that turned up a criminal record for rape and assault, prosecutor Rodolfo Rios told reporters.

"Investigating officers have located him (the suspect) and he is making a statement to their office about his possible involvement in this crime," Rios added.

On Tuesday authorities released security camera footage that appears to show three men near the building where the killings took place in Mexico City. They are seen leaving the scene calmly, and are believed to be suspects.  

Once seen as a sort of ceasefire zone -- or at least a place to hide out anonymously amid nine million people -- Mexico City suddenly seems a lot less safe since Espinosa was found Friday with a bullet through his head, his hands bound and his body showing signs of torture.

He was among the many Mexican journalists who had fled to the capital after receiving threats in their home towns.

The five bodies also included human rights activist Nadia Vera.

There are currently at least a dozen journalists from around the country sheltering in Mexico City because they fear for their safety in a nation where, according to Reporters Without Borders, at least 88 of their colleagues have been murdered in the last 15 years.