The 16-year-old son of Antonio and Dawn Armstrong who has been charged with murdering his father and mother allegedly tried to cover up his crimes.

The teenager called 911 from inside a closet to report that he had seen a masked man in his house and was hiding from the intruder.

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When police arrived, they found the handgun on the counter along with a note that read “I’ve been watching you,” but they were skeptical when the teen had to turn off an expensive alarm system to let them into the house and there was no sign of forced entry at the home.

Although investigators say the teen admitted to having experimented with silencing guns with blankets and pillows, he continued to deny he was involved in the murders. Both Antonio and Dawn Armstrong were found after having been shot with a pillow placed over them.  According to the Harris County Medical Examiner’s Office, the mother was shot twice in the head.

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Houston police have not yet determined a motive for the murder even as the teen continued to deny his involvement.

According to the Houston Chronicle, the Armstrong’s had a second child, a 12-year-old girl, who slept through the shooting and is safe.

‘It was kind of the All-American family, that’s why we’re trying to get down to figure out what’s going on in this household,’ HPD homicide detective Jimmy Dodson said.

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