Prosecutors in the State of Mexico, which borders Mexico City, suggest the grisly finds may not end there.

Since May 17, authorities have dug up the floors of the house where the suspect lived, and they plan to extend the search beneath several other rooms he rented out on the same property.

ID cards and other possessions from people who disappeared years ago were found at the junk-filled home, suggesting the killings may go back years.

The bone fragments found under concrete floors at the suspect's home would imply the corpses may have been hacked into tiny pieces.

That could make sense: the suspect, identified by prosecutors only as "Andres", was formerly a butcher and in fact sectioned and filleted his last victim.

Authorities have not released the 72-year-old suspect's full name under Mexican laws protecting a suspect's identity.

He has been ordered to stand trial in the killing of his last victim, a 34-year-old woman whose body he allegedly dismembered with a butcher's hacksaw and knives on May 14.

His capture was not the result of keen investigative work but because his most recent alleged victim was the wife of a police commander whom he knew personally.

He was to have accompanied the victim on a shopping trip the day she disappeared, so her husband suspected him when she failed to return.

The officer gained access to police surveillance cameras showing his wife had entered but not left the street where the suspect lived.

He went to the home, confronted the suspect and found his wife's hacked-up body inside.

Australian Associated Press