Seven inmates of Cook County, Ill. Jail were injured Monday during a brawl that involved knife play.

Jail officials say an altercation between two inmates quickly escalated along gang lines. Officials did not immediately say what prompted the fight, which occurred in the day room of the jail's maximum-security wing.

Authorities say one inmate involved in the fight allegedly crafted a home-made knife, which he used to stab three other inmates.

Three were taken to local hospitals where they were listed in stable condition. Four other inmates injured in the brawl were treated at the jail. No jail personnel were injured.

Authorities say the maximum-security wing is now on 24-hour lockdown.