SALTILLO - Police on Friday found the body of one of two recently-abducted Mexican journalists in Saltillo, northern Mexico, their newspaper reported online.

The body of Valentin Valdes Espinosa, a local news reporter, lay outside a hotel along with a warning message, in the city in northern Coahuila state, the daily Zocalo Saltillo said on its website.

The text said: "This will happen to those who don't understand," the Coahuila prosecutor's office said in a statement.

Brutal, competing drug gangs often send their adversaries grim warnings with written messages, beheadings or dismemberments.

Valdes' body bore five bullet wounds and signs of torture, the prosecutor's office said.

The other journalist, who was not named, was abducted with Valdes on Thursday night, and a third journalist who had been travelling in the same vehicle was not taken, according to the newspaper.

Mexico is one of the most dangerous countries in the world for the press, according to international rights groups.

A total of 13 journalists were killed in Mexico in 2009, according to a recent report by the Geneva-based Press Emblem Campaign (PEC).

Mexico's north has seen the country's worst suspected drug violence in the past three years, leaving more than 15,000 dead despite a military crackdown on organized crime involving some 50,000 troops.

Seventeen people were killed, including two men who were tortured and hung from a tree, in the past 24 hours in northern Chihuahua, the country's most violent state, local officials reported.