Former New England Patriots tight end Aaron Hernandez, charged with first-degree murder and held without bail, has been relocated to isolation for a month after a brawl with another another inmate at the Bristol County (Mass.) House of Correction.

He will spend 23 hours a day and eat meals in his cell, according to a report by NECN.

Hernandez was moved to the unit for 30 days as a result of a "physical altercation" in a common area of the jail, NECN.com reported Wednesday, citing the Bristol County Sheriff's Office. Usually, only one inmate is allowed in the common area at one time, and jail officials said they are reviewing the incident.

"I'm not happy that there may have been a breakdown in our system -- in our protocols," Sheriff Tom Hodgson said, according to the report. "When we have failures, the first thing we look at and I look at is, number one, how did this happen? And number two, how do we make sure this doesn't happen again?"

Hernandez, 6-1 and 245 pounds when he played for the Patriots, now must wear waist chains and leg irons when out of his cell. Previously, he had been allowed to be out of handcuffs at times, jail officials said.