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* Fan shot on night of Italian Cup final on May 3
* Roma-Napoli rivalry considered one of most heated in Italy
By Terry Daley
ROME, June 25 (Reuters) - The Napoli fan who was shot during violent clashes between supporters of his club and rivals AS Roma before last month's Italian Cup final has died overnight.
Ciro Esposito, 29, had been left in a critical condition at Rome's Gemelli hospital after being shot in the chest in the Italian capital on the night of the final on May 3, which Napoli won 3-1 against Fiorentina to secure their fifth Italian Cup.
"At six o'clock this morning, after a 50-day ordeal, our Ciro, a hero of the people, passed away," his family said in a statement.
"That damn May 3 our Ciro stepped on to the Via Tor di Quinto in Rome to save Napoli fans on a bus. Our Ciro heard the screams of children, who together with their families just wanted to go and watch a game of football.
"Ciro died to save others. We ask the institutions to do their part."
Rumours had circulated on Tuesday that Esposito had died, but those reports were revised when it was revealed that he had slipped into an irreversible coma with the announcement of his death coming on Wednesday morning.
"Ciro was a Napoli fan who wanted spend a joyous evening supporting his team. This tragedy should make everyone in football and the institutions that work with it reflect," Napoli president Aurelio de Laurentiis said.
"I and the football club express our most heartfelt condolences to his parents and family."
A notorious Roma supporter was arrested and charged with attempted murder after the incident, which set off ugly scenes in the stadium during a match attended by Prime Minister Matteo Renzi and watched by some nine million television viewers.
The kick-off of the game was delayed by 45 minutes as news of the shooting spread around the Olympic stadium, with Napoli fans pulling down their banners and a large chunk of their support watching the final in silence.
Spectators were treated to the unedifying spectacle of match organisers discussing what to do on the pitch in front of a baying crowd, before approaching hardcore "ultra" fan leaders to explain that Esposito had not been killed and was being treated in hospital in a bid to quell the unrest.
As they and Napoli midfielder Marek Hamsik made their way to the Napoli end of the stadium, they were pelted with flares and smoke bombs.
After the match, Napoli fans flooded the pitch, with a large group racing towards and making provocative gestures at the Fiorentina supporters at the other end of the ground.
Roma and Napoli fans are bitter rivals and the incident has fuelled deep resentment in Naples, the biggest club in Italy's poor south.
As well as repeated incidents of racist chants against black players, matches in Italy often feature chants aimed at Naples supporters, with rival fans calling them 'cholera-sufferers' and 'filthy Africans' or wishing the volcanic Mount Vesuvius to erupt over the city.
During Roma's 1-0 defeat to Juventus on May 11 a group of Roma fans in the Curva Sud section of the Olympic Stadium held up a banner in support of the alleged shooter.
Fan violence has long been a problem in Italian football, and authorities have tried a number of draconian measures to crack down on the trouble, including a controversial fans ID card scheme and banning of away fans for certain matches.
Many in Italy lament the inadequate organisation of major sporting events in comparison to similar occasions in other European nations, in particular England and Germany.
"We want those in charge of public order who made mistake to pay for them, in particular the Prefect of Rome who didn't ensure the safety of the Napoli fans," the Esposito family added.
"We ask the prime minister to ascertain the political responsibility for what happened. No-one can bring Ciro back but in his name we ask for justice rather than vengeance." (Editing by John O'Brien)