PHOENIX- Phoenix Police Department arrested an 18-year-old man Friday evening in west Phoenix when they found him in possession of a gun and his 15-year-old sister shot dead.

According to court documents, Ignacio Estrada admitted to officers that he was planning on killing his entire family for the last year because of a $20,000 loan he gave to his parents.

Ignacio considered tying up his younger sister, Reyna Estrada, but decided on shooting her so she wouldn’t be able to call the police after he shot and killed the rest of the family, according to court documents.

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The night before the shooting, court documents say, Ignacio took a 12-gauge shotgun from the trunk and hid it.

The next afternoon, while his parents were out of the house, he woke up and went to the living room where he fired into the direction of the bedroom his sister was in multiple times. The bedroom door was shut and locked.

During the interview with the police, Ignacio admitted to shooting and aiming blind.

Court documents say Ignacio returned to his room afterward and heard his sister moaning, so he shot through the door again, then waited for his father to come home from work.

When Ignacio’s father entered the house, Ignacio demanded his wallet and debit card and attempted to shoot his father in the head but the gun did not go off. He pulled the trigger another time and missed. The father and Ignacio engaged in a physical fight, according to court documents.

Ignacio’s mother returned home and saw the gun and the two men fighting she called 911, court documents say. When officers arrived on scene Friday evening, they found Ignacio and his father in a physical fight. Ignacio’s father was on top of Ignacio and Ignacio was still in possession of the gun.

Officers were able to kick the gun out Ignacio’s possession and arrested the 18-year-old.

Police are requesting Ignacio be charged with one count first-degree murder for killing his sister. He faces three counts of attempted first-degree murder for planning to kill the rest of his family. Additionally, he faces one count each of armed robbery, aggravated assault, kidnapping and burglary from vehicle, court documents say.

According to court documents, Ignacio was diagnosed with depression a couple of years ago but was not taking any medication, and he already had three active warrants out for his arrest.