NEW YORK (CBSNewYork/AP) — Prosecutors say a Russian immigrant has been jailed without bail after admitting he killed and dismembered his roommate in Brooklyn.

Sergey Mamonov appeared in court Wednesday to face a second-degree murder charge in the death of his roommate, 55-year-old Aleksandr Zilbergleyt.

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A criminal complaint says the 49-year-old Mamonov told police he beat his roommate to death during a fight on March 25 and carved up his body.

Authorities say Mamonov tried to dissolve the dismembered parts in vats of bleach. Some of the vats were found in the refrigerator of their Sheepshead Bay apartment along with bleach bottles and bones.

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“The guy had to be off his rocker. I don’t know, you know, to kill somebody is one thing, but to stay in the same apartment with a dismembered body,” said Glizer Valdez who lives across the street.

NYPD detectives went to the home earlier this week in response to a tip the roommate was missing.

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