The Italian, a previous offender originally from Frascati, was arrested on Friday after being caught on CCTV footage stabbing the Russian man in the chest on a street in the capital’s Prenestino district, La Repubblica reported.
The pair is said to have crossed paths as they returned from a music event to mark the May Day holiday.
The Italian man is reported to have held a grudge against the Russian over their arrest for a drug-related offence in Naples in 2009.
The Russian reportedly accused the Italian of involvement in the offence, which led to his arrest.
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