New York ( CNN ) -- A baby sitter was arrested after a 4-year-old boy was discovered dead on Wednesday in a luxury New York City apartment building , according to the New York Police Department . The child was found unconscious and unresponsive with visible bruising , cuts to his arms and legs and burns to his body , said Detective Markowski . ( NYPD policy is not to give out the full names of its detectives ) . He was pronounced dead at Roosevelt Hospital in New York . In a new conference , NYPD Commissioner Bill Bratton said the boy suffered `` horrific injuries sustained over period of days . '' The 28-year-old baby sitter has not been charged , according to NYPD Detective Ort . She did not confess to killing the boy , but police said she made statements to them that she abused the child . Julie Bolcer , a spokeswoman for the Office of Chief Medical Examiner , said the office is looking into the cause and manner of the death .
Boy , 4 , is found dead in a luxury apartment building in New York City . He had cuts , burns and visible bruising , authorities say . His baby sitter , 28 , has been arrested , but she has not been charged , police say .