RAY SUAREZ: Finally tonight, the ever more deadly war against the drug cartels in Mexico took a new turn this weekend, as Mexicans went to the streets to protest the violence.
Margaret Warner has that story.
MARGARET WARNER: The protests began last Thursday, when a few hundred people set out on a march from the resort city of Cuernavaca south of Mexico City. They were led by revered poet Javier Sicilia, whose 24-year-old son and six others were slain there in March in an altercation with drug cartel gunmen.
JAVIER SICILIA, poet (through translator): We are heading to Mexico City to demand that the authorities take a close look at this country, or it is going to go to hell.
MARGARET WARNER: As the crowd marched the 60 miles north to the capital, they were joined by thousands more, until tens of thousands swarmed Mexico City's main square yesterday. Some wore shirts saying "Enough bloodshed." Others held signs declaring, "No more bullets."
PROTESTER (through translator): I think the people will react to the march. Slowly, the people will become conscious of what is going on and, in cities all over the country, there will be reactions.
MARGARET WARNER: The protesters were decrying the violence that has claimed more than 34,000 lives since Mexican President Felipe Calderon launched a military offensive against the drug cartels in 2006.
The latest shock came two weeks ago, when authorities uncovered mass graves holding slain victims of the cartels, some of them apparently pulled off buses and brutalized -- 183 bodies were found in the northeastern state of Tamaulipas, just south of Texas. And at least 168 others were unearthed in the state of Durango.
But Calderon says he will keep up the pressure. In a speech last Wednesday, he declared, "Backing off from the fight is not an option. If we retreat, we are going to allow gangs of criminals to roam the streets of Mexico, attacking people, with no one to stop them."
Later that week, the government deployed hundreds of soldiers and federal police to northern Mexico, after cartel fighters attacked an army convoy outside of Monterrey. And just yesterday, Mexican marines battled gunman in a gang camp on a lake bordering Texas. One Marine and 12 gang members died.