Sunday evening in La Tour-du-Pin, in Isère, a man "had a somewhat surprising request".
"His neighbors asked him for a saw for a body to disappear," said Dietlind Baudoin, the prosecutor of Bourgoin-Jallieu, confirming information from the newspaper Dauphiné Libéré.
The magistrate opened an investigation in flagrante delicto for murder, entrusted to the research brigade of La Tour-du-Pin.
The victim, "more or less homeless", was then lodged by the tenant of the apartment, added the prosecutor.
This tenant and a friend present that evening have been in police custody since the arrival of the gendarmes on Sunday evening.
They were to be brought before an examining magistrate for murder.
The case was to be transmitted to the Grenoble investigation center on Tuesday for the probable opening of a judicial investigation.
According to the Dauphiné Libéré, the three men drank and quarreled on Saturday evening, then the 54-year-old homeless man received numerous stab wounds, causing his death.
It was while trying to get rid of the body, found wrapped in plastic film, according to the regional daily, that the two men of 34 and 50 years knocked on the neighbor's door, Sunday around 10 p.m.
The latter then warned the gendarmes.