CHICAGO (CBS) — A Chicago father shot and killed his 10-year-old twins and then turned the gun on himself, Chicago Police said Monday.

The murder-suicide happened in the 6200 block of North Richmond in Chicago’s West Rogers Park neighborhood early Monday morning. Police say the victims, a boy and a girl, were fatally shot in the back of the head by their 45-year-old father.

The 10-year-old boy has been identified as Mason Sanders. The 10-year-old girl has been identified as Addison Sanders. The father has been identified as Derrick Sanders.

The father died of a self-inflicted gunshot wound.

“[I heard] three loud bangs, long pauses in between. Woke me up at the first shot at 5:15 a.m. I felt vibrations all up and through my bed and I was in the top bunk,” said Leslie Lawrence, a neighbor who lives in the same complex.

Police say the mother of the children, who was estranged from the father, became concerned when their nanny could not get into their apartment and called the landlord.

A CPD Spokesman said the father had no prior history with the Chicago Police Department. Neighbors say they often saw the twins playing in front of the house, but had little interaction with the father.

This is a developing story.