The suspect, Mada Kabobo, 31, was taken into custody, Agenzia Giornalistica Italia reported
Britain's Sky News reported the attack appeared to have been random, with witnesses saying the assailant swung the digging tool wildly as he ran down the street..
The slain victim was identified as a 50-year-old man who was initially struck on the head and then hit some more when he fell to the ground, AGI reported.
Two of the surviving victims were seriously injured and two received less severe wounds, Sky News said.
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