Arizona wildlife officials say three endangered Mexican gray wolves, including two in New Mexico, died last month.
The Arizona Game and Fish Department said in a news release Friday that the latest incidents mean there have been four wolf deaths so far this year.
One from a pack in the Apache-Sitgreaves National Forest died after it was captured to replace a faulty GPS collar.
Another from a pack in the north-central area of the Gila National Forest was found dead.
The third wolf was a single collared one in New Mexico. Officials did not say in what part of the state it dwelled.
All the deaths are under investigation. Efforts to reintroduce the endangered wolves in Arizona and New Mexico have been ongoing for two decades.