Mexican authorities found the bodies of two men hanging from a footbridge that spans an avenue in this industrial city, capital of the northern state of Nuevo Leon, officials told Efe.

A spokesman for the State Investigations Agency said motorists traveling on Fidel Velazquez Ave., on the city's north side, alerted authorities to the find after midday Thursday.

State police and military personnel cordoned off the area to enable investigators to take down the bodies and begin their investigation.

These latest deaths exacerbated the latest wave of organized crime-triggered violence in Mexico.

Seven men were slain Wednesday night in a shooting in the northwestern state of Sinaloa while 14 others were found dead Thursday inside a van in the north-central state of San Luis Potosi.

San Luis Potosi state Attorney General's Office spokeswoman Gabriela Gonzalez told Efe that the group of 14 victims had apparently been kidnapped in Coahuila state, which is also in northern Mexico, and taken to San Luis Potosi.

Federal authorities said security forces conducting reconnaissance Thursday night in San Luis Potosi city's Lomas del Tecnologico district in the wake of the killings were attacked by organized criminals.

"In their own defense and for the safety of people in the area," they repelled the aggression and killed three of the attackers, the federal Attorney General's Office said in a statement.

In addition to those three deaths, the Defense Secretariat said the security forces arrested four suspected members of the Los Zetas drug cartel.

More than 50,000 people, according to official figures, have died in drug-related violence since late 2006, when newly inaugurated President Felipe Calderon militarized the struggle against organized crime.

The Movement for Peace with Justice and Dignity, which was founded by human rights activist and poet Javier Sicilia, puts the death toll at 70,000. EFE