CHICAGO (CBS) — Cook County State’s Attorney Anita Alvarez has suspended two prosecutors for failing to approve criminal charges against a man who had threatened to set his kids on fire after filling a bathtub with gasoline – then actually set them on fire three months later.

Nathaniel Beller, 29, doused his girlfriend, Taniya Johnson, and their two children with an accelerant on Dec. 29 and set them on fire. Johnson and their 4-year-old daughter, Nariya, died from their injuries, as did Beller. Their 9-year-old son, Naciere, was critically injured.

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Three months earlier, Beller filled a bathtub in his Cicero home and threatened to set himself and the children on fire, during a standoff with police.

He was arrested, but Cook County prosecutors did not approve any charges, and he was released.

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Alvarez ordered a review of that incident earlier this month, after Beller killed himself, his girlfriend, and their daughter.

On Tuesday, her office announced the two prosecutors who decided not to file charges against Beller in September have been suspended for 60 days without pay.

“When this tragic case came to my attention I had serious concerns about how it was reviewed for felony charges,” Alvarez said in a statement Tuesday night. “This office is entrusted with the awesome responsibility of charging persons with felony crimes and this can often be a complex decision making process for our Assistant State’s Attorneys who are on the front lines handling an extremely large volume of felony cases. But we must be accountable for our actions and, while there are many other questions to be answered by other agencies involved in this matter, I believe that I must discipline these employees for their role in the charging process.”

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The prosecutors were not identified.