Italian police have arrested two more Nigerian immigrants in their investigation into the brutal murder of Pamela Mastropietro, the Roman 18-year-old whose dismembered remains were found inside two suitcases outside Macerata in central Italy earlier this month.

Shortly after the murder, law enforcement officials arrested Innocent Oseghale, a 29-year-old Nigerian drug dealer, and afterward discovered blood-stained clothes, large kitchen knives, a cleaver, and other items belonging to the murdered woman in the man’s apartment. They immediately began a search for the man’s accomplices since various elements of the crime indicated the participation of more than one person.

On Saturday, police arrested two more Nigerian asylum-seekers, 22-year-old Lucky Desmond and 27-year-old Awelima Lucky, respectively living in Montecassiano and Macerata. One of the two men was reportedly fleeing toward the northern Italian region of Lombardy, which made the arrests all the more pressing.

The prosecutor of Macerata is charging the three men with murder, along with the sale of narcotics and the desecration and concealment of a corpse, based in part on a coroner’s report delivered Friday evening, which provided further details of the murder.

In the analysis of the woman’s mutilated corpse, investigators found that certain body parts were missing, including the victim’s neck and a portion of the genital organs.

The prosecutor’s office declared Saturday that the investigation was officially closed following the arrest of the three men believed responsible for the macabre crime.

Italian Minister of the Interior Marco Minniti has promised “severe punishments” for the guilty parties in the murder.

Over 620,000 migrants have entered Italy since 2013 with the majority still in the country, since borders to the north with France, Switzerland and Austria have been virtually shut down to prevent migrants from streaming north.

The immigration question is expected to be one of the decisive issues in Italy’s March 4 national elections, following on years of virtually unchecked mass immigration, mostly from northern Africa. The ruling center-left democratic party (PD) has spiraled down in popularity, due in large part to public perception that PD leaders facilitated the current migrant crisis.

In recent declarations, the leader of the Forza Italia Party, Silvio Berlusconi, said that the presence of so many undocumented migrants represents a “time bomb” for Italy, adding that the solution lies in deporting at least 600,000 migrants.

A 2016 study in northern Italy discovered a direct correlation between the number of migrants entering the country and the rise in the crime rate, with an increase of 0.4 percent in the crime rate for each increase of 1 percent in the number of immigrants in a given area.

The analysis conducted by the Confcommercio group revealed that the crime rate among legal immigrants is nearly double that of Italian citizens, while among illegal immigrants the crime rate soars to more than ten times that of citizens.

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