HARTFORD, Conn. (CBSNewYork/AP) – The prosecutor leading the investigation into last year’s massacre at Sandy Hook Elementary School said he will ask Connecticut’s courts to block the release of 911 tapes from the shooting by appealing a state Freedom of Information Commission decision.

The commission on Wednesday ruled unanimously in favor of The Associated Press, which sought access to records withheld by investigators. The recordings will not be made available immediately as Danbury State’s Attorney Stephen Sedensky III said the decision will be appealed in Superior Court.

“Any decision by the FOI Commission can be appealed in Superior Court and can be taken all the way to the Connecticut Supreme Court,” Tom Hennick of the FOI Commission told WCBS 880 Connecticut Bureau Chief Fran Schneidau.

The recordings could shed light on the law enforcement response to one of the worst school shootings in U.S. history. In all, 26 people, including 20 first graders, were killed inside the school on Dec. 14 by the gunman, Adam Lanza, who committed suicide as police arrived. Lanza also killed his mother, Nancy, at their Newtown home before the rampage.