I think that is very unlikely. If not in an enclosed high temperature incinerator, burning a human body releases a foul and distinctive odor.
Remembering from neighbors reports related to the Frenchtown, Montana double-homicides trial after which Caressa Hardy aka Glenn Dibley was convicted. While the two men's disappearance had been known for some time, it wasn't until years later that the convicted person's girlfriend reported they had been murdered. Neighbors remembered the smell from the burn pile years later.
Caressa Hardy — also identified in court documents as Glenn Dibley — is accused of killing two roommates in 2013 and then attempting to dispose of their bodies.
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