The five men were reportedly attacked by several tigers after traps they had set to catch game accidentally ensnared and killed a tiger cub. They rushed up into the trees by the rare, endangered animals.
According to Time, a sixth man died when a branch broke.
The men used their cell phones to contact nearby villagers, who called in authorities to help them drive the tigers away.
Sources told the BBC that the men were weak with hunger and had to be transported to the nearest village.
Sumatran tigers are found only on Sumatra Island in Indonesia. Only several hundred still survive in the wild.