CHICAGO (CBS) — A man suspected of setting his family on fire last weekend, had threatened to do it three months ago.

In September, 29-year-old Nathaniel Beller was involved in a standoff with Cicero police.

At the time, he filled a bathtub with gasoline and threatened to torch his children.

He was arrested and given a psychiatric exam but never charged.

Beller’s girlfriend and the mother of the children, Taniya Johnson, declined to sign a criminal complaint.

Last weekend, Chicago police say Beller doused Johnson and their children with a flammable liquid and set them on fire.

Johnson and their 4-year-old daughter died, along with Beller.

Their 9-year-old son is alive but badly burned.

A Cicero police spokesman said the department “strongly pushed” for felony charges to be filed but the Cook County State’s Attorney’s Office declined, CBS 2′s Brad Edwards reports.

Cook County State’s Attorney Anita Alvarez said the handling of the case is under review.

“If individuals in this office need to be held accountable for their judgment that will certainly occur,” she said in a written statement.

Neither Beller or Johnson had custody of their two kids. That fell to a foster parent who was supposed to supervise visits.

The foster parent allegedly wasn’t there when the fire occurred. The state’s Department of Children and Family Services is now investigating potential neglect by the foster parent.