LAS VEGAS (KLAS) — A fight between approximately 20 inmates at a Las Vegas-area prison Wednesday left four hospitalized, sources said.

At least four inmates were hospitalized after a fight inside High Desert State Prison on Wednesday, the 8 News Now Investigators have learned. One inmate required surgery, according to sources.

The fight began with a dispute over a telephone inside one unit, according to the Nevada Department of Corrections. Approximately 20 inmates from two gang-affiliated groups became involved, a spokesperson said.

An investigation is underway while the prison remains on a modified lockdown, according to the department.

The medium-security prison is located near Indian Springs, which is approximately a 45-minute drive north of Las Vegas. It is the same facility where a riot occurred in Dec. 2021, and a convicted murderer escaped nine months later.