A maximum-security inmate at the Arizona State Prison Complex - Florence in November 2009.

Matt York /The Associated Press/File

FLORENCE — Contraband alcohol produced by prisoners inside a maximum-security prison in Florence is believed to be the cause of suspected botulism poisoning of seven inmates, authorities say.

It’s believed that the suspected botulism results from alcohol made clandestinely by prisoners from fermented fruit, Pinal County and state Department of Corrections say.

The seven inmates were hospitalized and remain in intensive care after they became ill over the weekend, authorities say.

They’re housed in the Eyman complex’s Special Management Unit 1, and prison officials are closely monitoring the health of inmates in the same pod.

Senior Editor, News, Arizona Daily Star, Tucson, Az.