6 Priests Massacred in El Salvador : War: Jesuits, woman cook and daughter brutally slain. Thousands flee San Salvador in heaviest fighting since the offensive began.

Six Jesuit priests, including a leading human rights activist, were tortured and killed in San Salvador today as pitched battles raged on the fifth day of a leftist guerrilla drive to overthrow the U.S.-backed government.

Tens of thousands of the city’s residents fled from the fighting, pouring on to roads to escape the government’s attempt to retake rebel strongholds.

In one of the grimmest incidents in Central America in years, the priests, their cook and her 15-year-old daughter were killed in a garden at the Central American University early today while the capital was under the curfew.

The government condemned the killings and began an investigation, saying “terrorist groups” were responsible. But a Jesuit leader in the United States said the killings were part of a pattern of murder carried out by the military in El Salvador.

Father Walter Farrell, the leader of the National Organization of Jesuits, also said the priests had been tortured before they died.

Among the dead was university Rector Ignacio Ellacuria, an ardent defender of human rights and a leading proponent of liberation theology.

In Rome, Pope John Paul II appealed for an immediate end to the fighting, but the war continued and a math teacher at a university said one suburban battleground “looks like Beirut.”

At least 13 clergymen and lay religious workers have been killed since the civil war started in 1979, including three American nuns and one lay religious woman who in 1980 were raped and murdered. Five national guardsmen were convicted of that crime.

In the same year, Archbishop Oscar Romero was killed in the capital city as he said Mass. Former President Jose Napoleon Duarte later identified the assassin as a bodyguard for Roberto d’Aubuisson, leader of Salvador’s ruling ARENA party.

The murder of the six priests was apparently the first killing of religious figures in El Salvador since before the 1984 presidential elections brought in the Christian Democratic government of Jose Napoleon Duarte.

Duarte was succeeded in June by Alfredo Cristiani of the right-wing ARENA party.

Cristiani’s government has maintained throughout the fighting that it was in control, and the army radio early today proclaimed the defeat of rebels and the end to a civil war that has cost 70,000 lives.

But the rebels refused to quit and said on a radio broadcast that the killing of the priests would only make them fight harder.

The United States, which provides more than a $1 million a day to Cristiani’s government, said it was speeding delivery of military aid at El Salvador’s request.

The fighting in San Salvador today was described as the heaviest since the offensive began on Saturday. An air force plane flew over northern sectors firing high-speed machine guns at guerrilla positions, and powerful explosions thudded across the city of a million people.

Hundreds of residents swarmed out of the northern Mejicanos suburb carrying what belongings they could.