Police say Aston Barth, 33, confessed to strangling 35-year-old Jason Campbell during an argument in Barth's bedroom in his Central Islip apartment.
Barth allegedly told Suffolk detectives that he struck Campbell in the neck with an ax, post-mortem, in order to dismember the body.
Campbell was reportedly kept in Barth's bedroom closet for about a week before his mother and brother discovered the remains on December 24.
Barth is being held without bail in the Suffolk County Jail.
If convicted, Barth could face up to 25 years to life in prison.
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