By Serge F. Kovaleski
Washington Post Foreign Service
Tuesday, June 9 1998; Page A24

The killing of 11 leftist rebels over the weekend by an army patrol -- one of the bloodiest clashes in Mexico in nearly two years -- came at a time when the government is taking a sharply more aggressive stance against insurgents and their sympathizers.

Sunday's six-hour firefight between Mexican troops and members of the Popular Revolutionary Army in the town of El Charco, near the resort community of Acapulco, occurred less than a week after security forces raided a town in the southern state of Chiapas, arresting 167 people who they said were loyal to the Zapatista National Liberation Army, the country's largest guerrilla force.

The raid in the Chiapas town of Nicolas Ruiz was similar to two others launched since April in the villages of Taniperlas and Agua Tinta, both considered to be sympathetic to the Zapatistas.

Critics contend that the stepped-up military actions and the apparent antipathy shown by the administration of President Ernesto Zedillo toward mediated peace talks with the Zapatistas have for the time being precluded any possibility of an accord with the rebel group, which is seeking greater Indian rights. No peace negotiations are underway with the Popular Revolutionary Army, a Marxist group based in the southwestern state of Guerrero that emerged as a force in 1996.

An independent committee negotiating peace between the government and Zapatistas announced Sunday it was dissolving. It accused the government of promoting discord and weakening efforts toward reconciliation. The National Mediation Commission's decision followed the resignation of Bishop Samuel Ruiz as its president.

The commission said a military buildup in Chiapas, the violent breakup by authorities of "autonomous" pro-rebel villages and a government campaign to discredit the committee as sympathetic to the rebels had left its members no choice but to withdraw from the peace process.

"We have seen that the government continues to dismantle the necessary conditions for dialogue and negotiation," it said.

The government said today it would continue to push for peace in Chiapas, and it rejected charges that it was sowing discord.

In announcing his resignation on Sunday, Ruiz said there had been "constant and growing government aggression toward the diocese." He said priests were jailed on "false accusations," churches were occupied by the army and the diocese was wrongly accused of supplying arms to Zapatista supporters.

Meanwhile, Odilon Romero, the opposition mayor of the municipality of Ayutla, which includes El Charco, said in an interview today that members of the Popular Revolutionary Army had asked residents to attend an informational meeting in the town on Saturday afternoon. The session, which was peaceful, lasted into the night and the rebels decided to stay until morning at a schoolhouse.

But Romero said that someone alerted the army to the guerrillas' whereabouts, and at around 3 a.m. Sunday the troops launched their attack. One witness said four helicopters showered the school with bullets and explosives while soldiers exchanged fire with the insurgents. No army casualties were reported.

Today, large numbers of families were said to be fleeing El Charco and surrounding areas out of fear of the large military contingent in the town.

"I am trying to convince them that there is no reason to leave their homes or normal activities," Romero said. "But in reality, they are very scared of the heavy military presence."