Published: Jul 04, 2013 10:39 AM EDT

MIAMI (AP) - Miami-Dade County corrections officials say they are investigating a security breach that suddenly opened jail cell doors in a maximum security wing.
    
When the electronically controlled doors opened June 13 at the Miami jail, four inmates attacked a fifth inmate, who leapt from a second-floor tier to escape. The inmate who jumped remains hospitalized with injuries to his ankle and back.
    
The Miami Herald (http://hrld.us/14U3NPO ) has obtained internal corrections department reports about the breach. The agency's assistant director says 48 cell doors were open for less than five minutes.
    
Officials say a similar breach happened May 20, though no incidents involving inmates were reported.
    
The newly installed computerized sliding door system is part of an ongoing security upgrade. Investigators are looking at the control panel that operates the sliding doors.
    
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Information from: The Miami Herald, http://www.herald.com

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