Merced County's main jail was placed on lockdown Sunday night after a 36-year-old prisoner was stabbed six to eight times.Sheriff Mark Pazin said the prisoner, who he declined to identify, initially was treated at the Community Campus of Mercy Medical Center Merced and then transferred by ambulance to a Modesto trauma center. He had multiple stab wounds to the torso and a head injury. Pazin said the 6:30 p.m. incident has gang overtones, what he characterized as "stupidity at its finest." The Sheriff's Emergency Response Team moved the 12 inmates in Cellblock 3 to other cells while a search was made for the weapon. Jail commanders and Pazin will be meeting today to determine what sanctions will be imposed on the inmates. The sheriff's department Major Crimes Unit was summoned to investigate the stabbing, including a review of videotapes. Pazin was unsure how many prisoners were involved in the inmate's stabbing.