AP

Photographers Guillermo Luna Varela, left, and Gabriel Huge, right, were among four people found slain and dumped in plastic bags in a canal in Veracruz, Mexico on Thursday, May 3, 2012. A fellow journalist said Luna was Huge's nephew.

Three photojournalists who worked the perilous crime beat in Mexico's violence-torn Veracruz state were among four people found dismembered and dumped in plastic bags in a canal Thursday, less than a week after a reporter for an investigative newsmagazine was found dead in her home in the state capital.

The targeting of sources of independent information by two warring drug cartels threatens to add Veracruz to the growing list of Mexican states where fear snuffs out reporting on the drug war.

Reuters

Regina Martinez was found dead in the bathroom of her house in Xalapa on April 28, 2012.

The bodies of photographers Guillermo Luna, Gabriel Huge and Esteban Rodriguez were discovered in the town of Boca del Rio along with that of Luna's girlfriend, Irasema Becerra.

Regina Martinez, a correspondent for the national magazine Proceso, was found dead in her bathroom on Saturday with signs she had been beaten and strangled.

The London-based press freedom group Article 19 said in a report last year that Luna, Varela and Rodriguez were among 13 Veracruz journalists who had fled their homes because of crime-related threats. 

In total, more than 70 journalists have been murdered in Mexico in the last decade, according to the government-funded National Human Rights Commission. The latest grisly discovery came on World Press Freedom Day.

-- The Associated Press and Reuters contributed to this report

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Felix Marquez / AP

Police remove from a canal plastic bags containing the dismembered bodies of four people in Boca del Rio, Veracruz, on May 3, 2012. The fourth victim was Guillermo Luna's girlfriend, Irasema Becerra, state prosecutors said.