The brutal killing of an Indigenous family from the Mastanahua tribe in the Peruvian Amazon has local tribes on edge and authorities searching for answers.

The bodies of Shuri, his wife Elena, and mother-in-law, Maria, were found two weeks ago riddled with arrows near the charred remains of their maloca, or palm-thatched shelter, near the Curanja River in Peru’s Alto Purús region. Shuri’s second wife, Janet, has not been found and is presumed dead.

Shuri was his Mastanahua name, but he was also called Epa. The women’s names were given to them by Christian missionaries. Tribes living deep in the forest cut off from the outside world once were referred to as “uncontacted”—now they’re known as isolated tribes.

Shuri’s family lived near the