MEXICO CITY -- When federal agents patrolling the hilly back roads 100 miles from here captured a band of armed men wearing ski masks and uniforms last weekend, they suspected that they had found what people all over Mexico have feared since January: that the Zapatista National Liberation Army had moved beyond its southern stronghold and was spreading violence throughout the country.
That wasn't it at all, although who the eight men really represent isn't clear. Investigators say they are bandits who dressed as Zapatistas to gain the sympathy of residents where they were operating.
But relatives said the men had been beaten and forced to wear the masks in an elaborate scheme to justify the deployment of large numbers of government agents and troops to search the area for anti-government guerrillas.
The bandits were the latest in a series of rebel apparitions reported in Mexico since the Zapatistas staged their surprise attack at the beginning of the year. The violent outburst in the southern state of Chiapas, in which more than 100 people died, )) has made the possibility of other rebels much more real.
While no one can say for sure whether rebels are in other states besides Chiapas, the cumulative effect of the suspicions and false sightings is that as Mexico heads toward its highly uncertain presidential election on Aug. 21, the specter of violence seems to be growing.
Mexico City newspapers carry reports almost daily of the latest suspected rebel stronghold, often offering little proof other than accounts of frightened country residents who acknowledge that they aren't sure what they saw, but say that they know that the men they saw had guns.
Government attempts to squash the rumors have been ineffective, especially since many Mexicans remember that last year, the same officials also denied there was an armed movement in Chiapas.
A national poll of 9,500 people conducted last month by the Civic Alliance, a group of non-governmental organizations, found that two-thirds of those surveyed were afraid that violence would erupt if the election is not free of fraud. The governing Institutional Revolutionary Party has not lost a presidential election in 65 years, and the election of President Carlos Salinas de Gortari six years ago was believed to be fraudulent.
Sergio Aguayo, head of the alliance, said the reports of armed groups, substantiated or not, confirm the fears expressed in the polls and underscore how much more skittish Mexicans have become.
Tensions have been high since Zapatista leaders rejected the government's proposed peace settlement last month. The masked rebel leader who calls himself Subcommander Marcos said in newspaper interview that "there are armed groups in various parts of the country" and that violence could erupt if there is not enough progress in creating "a democratic opening" in Mexico before the election.
The Zapatistas have pledged to honor a cease-fire that has held since January and said that they would not interfere with the election.