© Suffolk County Correctional Facility NYPD officer Michael Valva, 40, charged on Jan. 24, 2020 with the second-degree murder of his 8-year-old son Thomas Valva. Right: Angela Pollina, 42, charged on Jan. 24, 2020 with the second-degree murder of 8-year-old Thomas Valva.

An 8-year-old boy with autism died of hypothermia last week after his NYPD cop dad allegedly placed him inside a freezing cold garage as temperatures dropped well below zero, officials said.

Suffolk County police arrested 40-year-old Michael Valva and his 42-year-old fiancee, Angela Pollina, on Friday for the second-degree murder of Thomas Valva.

Valva called the police on Jan. 17 to report that Thomas fell in the driveway of their home around 9:30 a.m. in Center Morchices, New York, while waiting for the school bus.

The child was taken to Long Island Community Hospital where his "body temperature was at 76 degrees," Suffolk County Police Commissioner Geraldine Hart said at a press conference on Friday.

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"Thomas Valva was subjected to freezing temperatures in the homes, unheated garage, overnight when the outside temperature was 19 degrees," said Hart.

As police investigated Thomas' death, Valva launched an online fundraiser to cover the cost of his son's funeral expenses. The community's donations to the now-defunct fundraiser surpassed Valva's requested $10,000 goal.

Police found that the injuries to Thomas' head and face were inconsistent with Valva's description on the 911 call and there was a history of reports to child protective services.

"Not only did they fail to render any type of meaningful aid, they lied to the police officers, they lied to the EMTs," Suffolk County District Attorney Timothy Sini told reporters on Friday. "This is one of the worse crimes...he died right in front of their eyes."

The medical examiner ruled the boy’s death a homicide and found that hypothermia was a major contributing factor, the Associated Press reported.

Suffolk County Judge Edward J. Hennessey ordered both Valva and Pollina held without bail. Their case will be presented to a grand jury and the next court date is on Jan. 29.

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Thomas' mother, Justyna Zubko Valva, told News12 Long Island that she begged a family court judge to remove their children from her ex's custody or they were "going to die."

"Every time I kept telling the judge, 'if you're not going to remove the children, they are going to die under his care and custody,'" said Zubko Valva to the station. "There was evidence, hard evidence. Reports filed. Children were telling me too about the abuse."

Valva has two other sons, ages 6 and 10, while Pollina has twin 11-year-old daughters and a 6-year-old daughter.

Sini said the 10-year-old and 8-year-old boys were both on the autism spectrum and were “at times forced to sleep in the garage.”

© File/Spencer Platt/Getty Images April 13, 2017 file photo of Suffolk County Police Commissioner Timothy Sini in Central Islip, New York.

Valva joined the NYPD in 2005 and, according to online records, he earned $100,000 in 2019. The transit cop has been suspended without pay, the police department said.

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If convicted, the couple faces 25 years to life in prison.

The community is expected to hold a vigil for Thomas at Kalers Pond on Sunday from 5 p.m. to 6 p.m.