A Nigerian street vendor Alika Ogorchukwu, 39, was beaten to death by an Italian, identified as Filippo Claudio Giuseppe Ferlazzo, in Civitanova Marche's busy town centre, a beach town on the Adriatic Sea, on Friday.
Ferlazzo became infuriated when Mr Ogorchukwu told the man's girlfriend she was beautiful, claimed Daniel Amanza, who runs the ACSIM association for immigrants in the Marche region's Macerata province.
'This compliment killed him,' Mr Amanza told The Associated Press.
'The tragic fact is that there were many people nearby. They filmed, saying "Stop", but no one moved to separate them,' Mr Amanza said.
The father-of-two's brutal death was filmed by onlookers who made no attempt to physically intervene - sparking outrage online.
Police in Italy arrested Ferlazzo, 32, for the murder of Mr Ogorchukwu, and allegedly stealing the victim's mobile phone, according to local agency ANSA.
Police used street cameras to track Ferlazzo's movements and arrested him on Saturday. Local media have reported that Ferlazzo is currently being held in the Montacuto prison in Ancona. It is claimed he will not be charged with racism.
'The situation is quite clear, everything seems to have emerged from a dispute over frivolous reasons, not racism', said Matteo Luconi, one of the investigators.
Alika Ogorchukwu, 39, (pictured here) was beaten to death by an Italian man, identified as Filippo Claudio Giuseppe Ferlazzo, in Civitanova Marche's busy town centre on Friday
People protest where the Nigerian street vendor Alika Ogorchukwu has been murdered, in Civitanova Marche, Italy, on July 30
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