MISSOULA, Mont. (AP) -- State wildlife officials say pneumonia has been confirmed in a herd of about 300 bighorn sheep west of Anaconda.

Fish, Wildlife and Parks biologist Ray Vinkey collected samples from four members of the Lost Creek herd that were shot on Aug. 20 because they exhibited signs of being ill. Tests at the FWP lab in Bozeman confirmed the diagnosis.

This is the sixth herd to suffer a pneumonia outbreak since late last fall. Most recently, FWP confirmed pneumonia in the Skalkaho population east of Hamilton on Aug. 9.

Copyright 2010 The AP.