Two loggers have been killed by bow and arrow after allegedly encroaching the land of the uncontacted Mashco Piro Indigenous tribe deep in Peru’s Amazon, according to a rights group.

The group, known as FENAMAD, defends the rights of Peru’s Indigenous peoples. It says tensions between loggers and Indigenous tribes are on the rise and more government protective action is needed.

Two other loggers in the attack were missing and another was injured, FENAMAD said, and rescue efforts were underway.