Authorities in northeastern Arizona say a sheriff's deputy used a stun gun to drive off a large cow that was stepping on him in a field after he rescued another person pinned to the ground by the cow.

The Navajo County Sheriff's Office said on Tuesday that a female telephoned for help while pinned on Friday as the cow was "continually pressing her" if she moved or tried to get away.

A statement said the deputy used his stun gun to get the cow to release the woman but that it then charged him, striking his chest and forcing him to the ground before he was able to again use his stun gun to drive away the cow.

Paramedics examined both people but they refused further medical attention.