Lewis, 32, pleaded guilty in March to one count of murder in the second-degree.
The Westchester County District Attorney's Office said that on Feb. 10, 2014, at approximately 9 a.m. Gruber went to the Dole Senior Center in Mount Vernon via the Senior Center bus. At 2:30 p.m. the bus dropped Gruber off at her home. That was the last time anyone saw Gruber alive, the D.A.'s office said.
Concerned neighbors and relatives began searching for the victim without success. The next day, a worried grandson, went to Gruber’s house looking for her. On Feb. 11, a relative filed a Missing Persons Report with Mount Vernon Police.
The next day, Mount Vernon detectives went to Gruber’s house to and found her body at the bottom of the basement stairs, under a large pile of clothes and a piece of plywood, the D.A.'s office said. A nearby 2x4 piece of wood had the victim’s blood on it, according to the office.
The victim’s death was later ruled a homicide by blunt force trauma to head and body, the DA's office said.
The investigation revealed that Lewis had been selling various items taken from Gruber's residence, according to the D.A.'s office.
The police investigation determined that Gruber walked in on Lewis, who was burglarizing her home.
Lewis was arrested in July, 2014 on the murder charge. He was already in custody since March 3, 2014, on an unrelated burglary charge.
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