Would the slaying of the silver-haired American nun, who devoted her life to fighting land grabbers and loggers in the Amazon, galvanize action and world opinion the same way the killing of legendary Brazilian rubber tapper Chico Mendes did 16 years ago?

Officials and activists are already drawing comparisons between Mendes, a national hero here, and Stang. The 73-year-old nun was gunned down Saturday in the jungles of northern Brazil, a region beset by land disputes and growing lawlessness. Authorities say the Ohio-born Stang was ambushed by hit men contracted by a local rancher, just as Mendes was assassinated on the orders of a wealthy landowner he had opposed.

Both Stang and Mendes were beloved figures in the rural communities where they organized poor residents to stand up to powerful economic interests that threatened to push them off the land.

Environmentalists credit Mendes with focusing attention on the plight of men who harvest sap from rubber trees and on the wanton destruction of the rain forest. Stang for decades championed the cause of poor farmers in their battles with ranchers and loggers intent on claiming vast tracts of jungle.

Brazil's rain forest, the world's largest, has swiftly diminished in size as loggers and large landowners expropriate land and clear wide swaths. Last year alone, forest territory the size of New Jersey was lost.

Mendes' death sparked international outrage. So too has the killing of Stang, whose kindly, bespectacled visage made newspapers around the world and who is being lauded as a martyr for the cause of sustainable development in the Amazon.

Some activists are cautiously optimistic that the tragedy will put pressure on Brazil to take firmer action in a region where weak government has created a bloody power vacuum.

"We're hopeful that the government will take a stand against the large farm owners, [who] have shown how they act," said Tarcisio Feitosa, a member of the Roman Catholic Church's land commission in Para state, where Stang worked. "It was a planned killing, and the government must show these land mafias in the region how it will address the situation."

Police were looking for at least three suspects in the slaying: two gunmen and the man who allegedly hired them.

In Brasilia, the nation's capital, government ministers convened an emergency meeting Tuesday to discuss options, which include declaring Stang's killing a federal case and dispatching army troops to help stabilize the situation. The presidential palace announced that President Luiz Inacio Lula da Silva, on a visit to neighboring countries, would cut short his trip and return to Brazil early to follow the case more closely.

Brazilian media also said authorities — stung by accusations of indifference toward Stang's reports of death threats against her and other activists — would increase the number of police and environmental officers in the area to help crack down on landholders who have improperly laid claim to forest land.

In recent weeks, woodcutters and ranchers in Para have escalated their opposition to environmental-protection measures by blocking roads and waterways and threatening to close down ports. In response, the government quietly restored some suspended logging permits.

With Stang's slaying, however, officials have political cover to take a harder line toward loggers and speculators and to promote agrarian reform, environmental advocates say.

"This can reinforce the Brazilian government's commitment to changing business as usual in the Amazon, especially in Para. It's as clear and tragic an illustration as you can imagine of the extent to which that region is a no man's land," said Stephen Schwartzman of the New York-based group Environmental Defense.

Schwartzman said he was encouraged by government plans to establish a group of sustainable-development reserves in Para's Terra do Meio region. Also promising, he said, is the governor's willingness to work with federal officials on preserving the forest, which includes cedar and mahogany.

The problem is often collusion between corrupt local authorities and the ranchers and loggers, according to officials and environmentalists. More people die from land conflicts in Para than in any other state, and most cases go unresolved.

Environmentalist Adriana Ramos of the Instituto Socioambiental said she was troubled by official statements Tuesday implying that Stang was killed in response to government action in Para. It was precisely government inaction, she asserted, that allowed the tragedy to happen.

"The government has to at least offer security," Ramos said.

Stang's goal was to have the area around Anapu, the town where she lived for more than 20 years, declared a sustainable- development reserve. She was on her way to a meeting with local settlers when two gunmen confronted her. Witnesses reported that Stang took out her Bible and was reading aloud from it when the men pumped at least six bullets into her.

She was buried Tuesday in Anapu, a small town about 200 miles southwest of Belem, the state capital. At least 2,000 people attended the rites, news services reported.

"If the government wanted to honor her memory, it would take them 15 minutes," said Nilo D'Avila, a Greenpeace coordinator. "They would [just] have to sign the two sustainable-development projects she was working for."

Other activists stress that preservation of the Amazon is a long-term task. After Mendes' assassination in late 1988, Schwartzman noted, it was years before his associates assumed political power in the western state of Acre, where sustainable development is now an article of faith.

Faith was what drove Stang, a member of the Sisters of Notre Dame de Namur, a Catholic order, to move to a country thousands of miles from home in the mid-1960s, said her youngest brother, Tom Stang, 67, a Los Angeles resident.

His sister had been aware of the dangers but was unfazed, he said.

"We knew she wanted to die with her boots on," he said. "Even in retirement, she was doing whatever she could to help people unite and struggle and claim their human rights."