Three Mexican gray wolves have been found dead in Arizona and New Mexico and wildlife managers say they're investigating.

The latest monthly report on the status of the endangered predators shows a male wolf belonging to the Marble Pack was found dead in New Mexico. In Arizona, a female from the Hoodoo Pack and a single male were also found dead in June.

The Arizona Game and Fish Department didn't release any further details about the deaths in the report released Friday. The agency partners with the U.S. Fish and Wildlife Service on the wolf reintroduction program.

Illegal shootings, politics and legal battles have hampered the program over the years. Environmentalists want more captive wolves released, but ranchers and some local leaders are concerned about livestock losses and public safety.