Electrical Explosion Causes 'Extensive Damage,' Inmate Evacuation At Middleton Jail

MIDDLETON, MA — An electrical explosion that forced the evacuation of 407 inmates at the Middleton Jail and House of Correction caused "extensive damage" and forced the transfer or relocation of inmates, the Essex County Sheriff's Office said on Wednesday.

Visitation remains suspended until at least Monday, while attorneys are allowed to meet with inmates on site.

The spokesperson said the explosion appears to have happened in an underground conduit connecting the largest housing unit in the county. About half of the inmates were evacuated to other buildings.

One injury described as minor was reported in the hours after Tuesday night's blast.

The 240 Building sustained "significant" damage and remained without power as of Wednesday night. The assessment of the building is expected to take several days before it is determined whether it can be brought back online.

"The safety and security of everyone at Essex County Sheriff's Department facilities is my top priority," Sheriff Kevin Coppinger said in a statement on Wednesday. "While this is a complex situation, it is well under control thanks to the professionalism of our officers and staff."

Coppinger thanked the state's other sheriffs for their offers of assistance and the Middleton Electric and Fire departments for their responses and support.

Additional Essex County Sheriff's Department personnel are on duty in an attempt to ensure the safety and security of inmates and staff, the Sheriff's Office said.

(Scott Souza is a Patch field editor covering Beverly, Danvers, Marblehead, Peabody, Salem and Swampscott. He can be reached at Scott.Souza@Patch.com. X/Twitter: @Scott_Souza.)