How an NYPD Officer's Home Security Cameras Led to His Arrest for Allegedly Killing His Son, 8

A New York City police officer and his fiancée, who were accused of letting his 8-year-old son with autism freeze to death, were allegedly caught on their home security cameras taunting the boy for being cold before he died.

On Jan. 17, Michael Valva called Suffolk County police to report that his son Thomas had fallen in the driveway of his Long Island home while waiting for the school bus.

However, investigators found inconsistencies with Valva’s story and believe Thomas had allegedly been forced to sleep in the family’s garage overnight in sub-freezing temperatures, allegedly killing him, Suffolk County Police Commissioner Geraldine Hart said at a press conference on Jan. 24.

Now, Valva and his fiancée Angela Pollina are charged with second-degree murder. They have pleaded not guilty.

On Friday, during the couple’s arraignment, prosecutors revealed that home security cameras used by the pair to monitor their children also recorded the final days of Thomas’s life, according to the New York Times, PIX11 and WNBC.

RELATED: NYPD Officer, Fiancée Allegedly Murdered Son With Autism by Leaving Him Overnight in Frigid Garage

The camera found in the garage was labeled “kids room” and two nights before Thomas’s death, recorded him and his older brother, Anthony, 10, shivering as they slept on the floor of the freezing garage, Assistant District Attorney Laura Newcombe said.

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“They are on cold concrete. There are no pillows, no blankets, no mattress,” Newcombe claimed during the hearing.

On the day of his death, Thomas was allegedly falling over and “face-planting” on the garage’s concrete floor, Newcomeb said.

In an audio recording from that morning, his brother can be heard asking why Thomas was having troubling walking.

“When you’re washed with cold water and it’s freezing, you get hypothermia,” Michael Valva responds, Newcombe said, citing the recording.

Later, when asked why Thomas was falling, Michael Valva allegedly says, “Because he’s cold. Boo f–king hoo.”

Pollina then asks Michael Valva, “What are you doing?” to which he can allegedly be heard replying, “Suffocating him, that’s what I’m doing,” Newcombe said.

“Take your hands off his mouth,” Pollina tells him, Newcombe said, citing the recording. “There are people everywhere.”

Since losing custody of her sons two years ago, Thomas’ mother, Justyna Zubko-Valva, has fought to prove they were the victims of abuse, the Times reports. She chronicled her fears for her sons on her Twitter page StandUpAgainstChildAbuse.

Valva and Pollina have pleaded not guilty. The couple’s attorneys could not be reached for comment Tuesday.

If you suspect child abuse, call the Childhelp National Child Abuse Hotline at 1-800-4-A-Child or 1-800-422-4453, or go to http://www.childhelp.org. All calls are toll-free and confidential. The hotline is available 24/7 in more than 170 languages.