Mada 'Adam' Kabobo, 31, who illegally entered Italy in 2011, is accused of killing three men, ages 64, 40 and 21, and injuring two others during an hour-long rampage before he was stopped by police, Italy's ANSA news agency reported.
Kabobo later told psychiatrists that he heard voices from Africa that told him to carry out the killings.
Psychiatrists told a presiding judge Kabobo is "able to understand" the charges against him, and his ability to control his actions was "greatly diminished but not totally absent" at the time of the attack.
The judge ultimately deemed Kabobo fit for trial.
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