(CNN) -- The nonprofit that pushed last month for Venezuelan officials to investigate reports of a massacre in an Amazon indigenous community said Monday that it now believes there was no attack there.
"Having received its own testimony from confidential sources, Survival now believes there was no attack by miners on the Yanomami community of Irotatheri," said Stephen Corry, director of Survival International.
The statement comes after Venezuelan state media over the weekend published several reports detailing officials' accounts from the area, also concluding that no massacre had occurred.
An aerial flyover and ground operation to the community in a remote region along the Brazil-Venezuela border showed no signs of an attack, Venezuelan Brig. Gen. Jesus Zambrano told state-run VTV.
"We can testify that nothing happened," he said. Investigators "also visited other communities in the region, before reaching Irotatheri, and also nothing happened there."
On Saturday, Venezuela's government ombudswoman said the report was fueled by second-hand hearsay.
"It was a false, biased report," Gabriela Ramirez told reporters. "The report was made by an indigenous person that heard that another organization had said it."
Last month allegations of the reported massacre trickled out of the area, where unauthorized Brazilian gold miners have long clashed with indigenous groups.
A declaration on the Survival International website last month said members of a neighboring indigenous community had heard reports of a massacre from Irotatheri's residents. The declaration, purportedly from a group of organizations representing indigenous people and communities in the Amazon, said of about 80 Yanomami people who lived in the Irotatheri community, only three survivors had reportedly been found.
Survival International, which advocates tribal peoples' rights worldwide, had described it as an "atrocity."
In his Monday statement saying that Survival no longer believes there was an attack, Corry said visitors to the area "had heard stories of a killing in July."
"We currently do not know whether or not these stories were sparked by a violent incident, which is the most likely explanation, but tension remains high in the area," he said.
Venezuelan officials said last Wednesday that they were investigating the reports of an attack. Several days later, a top official said visits to the region revealed that reports about the alleged massacre were false.
On Saturday, a report from Venezuela's AVN news agency said investigators from Venezuela's air force concluded that "levels of illegal mining in the area were minimal."
On Monday, Corry disputed that claim, saying "many illegal gold miners are currently operating" in the area.
"The Venezuelan government's reaction remains shameful. It has not said, even now, that it will remove the miners, and it immediately denied having found 'evidence' of killings, before even concluding its own investigation," Corry said.