A serial killer who preyed on his elderly neighbors in a public housing development has pleaded guilty to three murders in exchange for a sentence of 30 years to life in prison, prosecutors say.

Kevin Gavin, 71 of Brooklyn, pleaded guilty to one count of first-degree murder and three counts of second-degree murder on April 24, for the killings he committed from 2015 to 2021 in the New York City Housing Authority’s Carter G. Woodson Houses, Brooklyn District Attorney Eric Gonzalez said in a statement. The victims trusted Gavin for help with running errands and repairs, the district attorney's office said.

Gavin, who lived in the same building, killed Myrtle McKinney, 82, in 2015; Jacolia James, 83, in 2019; and Juanita Caballero, 78, in 2021. He was caught after he used Caballero's debit card, authorities said.

Discover WITNESS: Access our exclusive collection of true crime stories, podcasts, videos and more

After his arrest in 2021, Gavin confessed to all three murders, the district attorney's office said.