SPRINGFIELD, Mo. (AP) — Authorities in southwestern Missouri’s Greene County say a jailer is recovering after being seriously injured during an alleged assault by an inmate.

Sheriff Jim Arnott says the unidentified deputy serving as a corrections officer during the Saturday altercation sustained a broken nose, fractured jaw, a concussion and cuts that required staples on his head to stop the bleeding.

The sheriff’s department’s statement did not identify the inmate or offer details about what prompted the reported assault that Arnott called “a horrendous event.”

Arnott says the matter remains under investigation, and no charges were filed as of late afternoon Monday.