Hundreds of thousands of protesters gathered in the Zocalo
Newspaper columnists in Mexico have reacted to the announcement that Andres Manuel Lopez Obrador has been elected president of an "alternative" government by his supporters with a mixture of bemusement, unease and cynicism.
Writing in La Cronica de Hoy, Juan Manuel Martínez is simply pleased that "at least the institutions haven't gone to the devil".
"However tortuously, they have been able to carry out their work. Nevertheless, we are far from resolving this political dispute."
An editorial in Uno mas Uno describes the latest developments in the Lopez Obrador camp as "a fantastic theatre of chatterboxes" and compares the officially defeated candidate as "like Napoleon Bonaparte in his epoch".
"He has crowned himself 'Legitimate President of Mexico'... and his government will be without any institutions as he has sent them all to the devil."
Commenting in Excelsior, Rene Aviles Fabila accuses the Lopez Obrador camp of "abandoning the dignity of the political struggle and concentrating on the lowest kind of street punch-up".
The writer accuses Mr Lopez Obrador of being "surrounded by crooks and the disaffected," and asks whether he intends to dismantle the old system and replace it with one run by the "corrupt and muddled intellectuals".
Backing for the Lopez Obrador cause comes from Rosa Albina Garavito, writing in the centrist El Universal.
She argues that the latest developments "herald a new stage of peaceful civil resistance to the legal but illegitimate imposition of a [new] president".
"In every stage of our history, a people mobilised in the legitimate defence of its interests has achieved the country's social, political and economic progress.
"No progress has ever been achieved as a concession from the governing class."
Manuel Mejido, in El Sol de Mexico, is uneasy about the overall situation, and calls on the ruling sectors in Mexico "to take seriously" many of the issues raised by the Lopez Obrador supporters "because they represent the poor, the majority and marginalised bulk of society. Sixty eight million hungry Mexicans".
An editorial in the leftist La Jornada warns there will be no peace for the incoming government of President-elect Felipe Calderon, which will be "severely wounded" from the outset.
And the well-known political analyst Pablo Gonzalez Casanova, writing in the same paper, accuses Washington of openly supporting a massive electoral fraud perpetrated by the government and party of President Vicente Fox, "the former chief of Coca Cola".
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