Police found the body of Regina Martinez on Saturday inside the bathroom of her home in the Veracruz state capital, Xalapa. There were signs of heavy "blows to her face and body," and initial evidence suggested she died of asphyxiation, the state Attorney General's Office said in a statement.

Martinez was the Xalapa correspondent for Proceso, one of Mexico's oldest and most respected investigative newsmagazines, and she often wrote about drug cartels in Veracruz, which has seen escalating violence committed by warring drug gangs. Proceso said in a story on its website that she had worked for the magazine for 10 years.

Authorities provided no possible motive for her killing, which was the third involving a journalist in Veracruz over the past year.

The National Human Rights Commission issued a statement Sunday decrying violence against journalists. Such violence "also violates the right of all people to be adequately informed," it said. "This independent body will follow the actions of the authorities and investigations to solve this act."

Veracruz government spokeswoman Gina Dominguez said agents were searching Martinez's home for evidence.

"All lines of investigation will be exhausted. The fact that she was a journalist is one of them," she told The Associated Press.

Recently Veracruz has been plagued by cartel violence, some of it between the powerful Zetas and the so-called Jalisco Cartel New Generation, which is believed to be linked to the Sinaloa cartel. The coastal state is also on a human trafficking route north to the United States.

Veracruz

Gov. Javier Duarte has ordered an exhaustive investigation into Martinez's death, he said in a statement.

Police found her body after receiving a tip from a neighbor that her house had been left open since early in the day.

In addition to Martinez, at least two other journalists have been found dead in Veracruz in a year, and none of the cases has been resolved.

In July 2011, a reporter on police matters with the newspaper Notiver, Yolando Ordaz de la Cruz, was found with her throat cut. A month earlier, gunmen killed Miguel Angel Lopez Velasco, a columnist and deputy editor with Notiver, as well as his wife and one of his children.

Media watchdogs consider Mexico one of the most dangerous countries in which to be a journalist.

There is disagreement on the number of journalist killings. Mexico's human rights commission says 74 were slain from 2000 to 2011. The New York-based Committee to Protect Journalists says 51 were killed in that time.