Members of the Ku Klux Klan yelled as they flew Confederate flags during a rally at the statehouse in Columbia, South Carolina July 18, 2015. Reuters

Ian Rubin, a white man who reportedly claimed to be a "mafia hitman" while threatening a mob-styled lynching of two black people last month in New York City, was indicted on hate crime charges and sent to a maximum-security prison, the New York Daily News reported Thursday.

Rubin was arrested Feb. 21 after threatening black residents in his Brooklyn apartment complex with a knife on multiple occasions, Assistant District Attorney India Sneed said in Brooklyn Supreme Court Wednesday.

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Rubin, a convicted felon, was previously charged with second-degree assault in Florida. He allegedly approached a black man and said, "I did time in the penitentiary, you are going to die today."

People hold placards at an anti-racism protest outside of the U.S. Embassy in London, Britain, Nov. 9, 2016. Reuters

He "threatened two people with a knife, saying he’s going to kill a n----r tonight," Sneed said Wednesday. Rubin believed black people living on the fifth floor of his building were "heroin addicts" who were "plotting against" him, according to his conversations with detectives after being placed in custody.

He then told authorities he was "a hitman for the Mafia and that the Mafia likes to kill and lynch n-----s, and [Rubin] would have the Mafia chop up [the victims]," court documents revealed.

Rubin's request to lower his cash bail was denied after pleading not guilty to the February charges. He will reportedly be held in Rikers Island until May 3, when he’s expected to make his second court appearance since last month.

Hate crimes have been on the rise across the U.S. since 2015, as the number of hate groups has also surged to at least 917 nationwide in 2016. Meanwhile, 867 bias-related incidents occurred in a span of just 10 days following the election of President Donald Trump, the Southern Poverty Law Center reported in February.

Rubin's misdemeanor charges carry a maximum sentence of one year if he's convicted.