Police on Sunday charged a 48-year-old man, Daniele De Santis -- who has already served bans for football-related violence -- with attempted manslaughter after he allegedly shot three fans prior to the violence-marred Cup final between Fiorentina and Napoli on Saturday.

The most serious shooting victim, 30-year-old Ciro Esposito, remains in hospital after undergoing delicate surgery to remove a bullet, allegedly shot from a Beretta gun used by De Santis, from close to the victim's spinal cord.

However, reports on Tuesday said initial tests comparing residue found on De Santis's hands and the bullets have proven inconclusive.

De Santis, a hardline Roma fan who allegedly shot at a group of Napoli fans when they reacted angrily to his provocations, has denied the shooting.

"It wasn't me who shot," he is quoted as saying in Gazzetta dello Sport.

Following the incident De Santis was beaten by several Napoli fans and later taken to hospital, where he was later interrogated by police before being charged.

Reports claim a gun allegedly used by De Santis was found by a woman, Donatella Baglivo, only metres away from De Santis as he lay prone on the ground.

She is quoted as saying: "I found the gun and threw it behind a bin to keep it out of harm's way, then I immediately told the police."

She is set to be interviewed for a second time by investigators, according to a report by domestic news agency ANSA.

The incident adds to the long list of football-related violence between fans of rival Italian clubs.

Yet, the events which followed inside Rome's Olympic Stadium, where Napoli beat Fiorentina 3-1, have caused as much grief and embarrassment.

New Italian Prime Minister Matteo Renzi was among dozens of high-ranking officials who watched as the final was delayed for 45 minutes after news of the shootings filtered through to Napoli's Curva Nord (North End).

Hardline supporters often hold great sway within major clubs and it is alleged they ordered Napoli not to play.

When rumours that a youth had been killed by police spread like wildfire during a Roma v Lazio derby in 2004, fans rioted and, after Roma captain Francesco Totti spoke to ultra leaders, the authorities called the game off.

During Saturday's delay, Napoli captain Marek Hamsik was ushered over to speak with ultra leader Gennaro De Tommaso, who was holding court at the front of the stands.

Also known by the gruesome nickname Genny 'a Carogna (Genny the carcass), De Tommaso is the son of an alleged Camorra mafia boss, Ciro De Tommaso. In recent days his picture has been splashed all over Italian media.

Maurizio Gasparri, a vice-president of the Italian Senate, said: "In addition to whoever shot the victims, people like Genny 'a Carogna should be jailed immediately. They have made a mockery of the State."

De Tommaso has been portrayed as the man who held an impotent Italian State in his hands for a short time, and calls to introduce tough, new anti-hooligan laws have since been gathering momentum.

Giovanni Malago, the president of the Italian Olympic Committee (CONI), on Tuesday called for Italy to look to the tough, anti-hooligan laws introduced to Britain in the 1980s by former Prime Minister Margaret Thatcher.

"Look at how Thatcher dealt with the hooligans. Full stop," said Malago. "This is how we have to deal with this. I'm not a lawmaker, but this is what we have to do."

Italian football federation (FIGC) president Giancarlo Abete admitted: "It's a matter of fact: in the stadiums ultras play an unacceptable role."