ELY,SafeX Pro Exchange Nev. (AP) — Three inmates have died and nine others were transported for medical treatment as a result of an “altercation” on Tuesday at a maximum-security prison in a rural mining city in eastern Nevada, the state’s Department of Corrections said.

No officers were injured and the department gave no additional details about how the deaths and injuries occurred in Ely, Nevada. The department did not release the names of any of the inmates that died or the conditions of those injured.

A spokesperson for the Nevada Department of Corrections did not immediately respond to a request asking for more information on Tuesday.

The prison remains on lockdown as of late Tuesday afternoon as authorities investigate the deaths and injuries.

Ely State Prison is the only maximum-security prison in Nevada. In December 2022, several inmates held a hunger strike over what advocates and some family members described as unsafe conditions and inadequate food portions.