Under pressure by Mexicans and investors to end a smoldering, year-old peasant rebellion, President Ernesto Zedillo has ordered its leaders arrested, accusing them of plotting violent attacks across Mexico.

Zedillo's surprise announcement Thursday was a reversal of the government's policy of trying to make peace with the Zapatista National Liberation Army by promising to help the poor and clean up Mexican politics.The president, in office since Dec. 1, has been under intense pressure to reassure investors about Mexico's stability - especially after a currency crisis erupted in mid-December, slashing the peso's value by 40 percent and throwing the economy into chaos.

In the southern state of Chiapas, scene of the peasant uprising, at least 200 to 250 soldiers, accompanied by an armored vehicle with a 90mm gun, guarded the village of San Andres Larrainzar Thursday night.

Zapatista fighters told reporters they were going on "red alert." The guerrillas cut down trees and dug trenches along roads leading into rebel territory.

In a nationwide TV address, the president said police on Wednesday found weapons caches in Mexico City and the Gulf Coast state of Veracruz and plans for "new and greater acts of violence" across Mexico.

The president did not offer any evidence of those plans. The caches contained a variety of firearms, ammunition, grenades and explosives but were not large by military standards.

Subcommandante Marcos, the rebel leader and spokesman, and five other rebel leaders had been identified, the president said. Arrest warrants were issued for them and seven others on charges including sedition, treason, terrorism and possessing military weapons banned for civilian use.

The Jan. 1, 1994, uprising by impoverished Indian peasants embarrassed the government the very same day that Mexico, Canada and the United States launched the North American Free Trade Agreement.

At least 145 people were killed.