Anna Alvazzi del Frate, research director of the Geneva-based Small Arms Survey think-tank, told reporters that mafia killings in Italy dropped by 43 percent between 2007 and 2010, and that the trend was continuing.

"We think that this may be related to the increasing involvement of mafia groups in business relations, for example through money laundering, including involvement with the white-collar sector," Alvazzi del Frate said.

According to the Small Arms Survey's annual study – which provides snapshots of firearms issues around the globe – the risks of using extreme violence now appear to outweigh the perceived benefits for Italy's crime syndicates.

"This may lead them to avoid visibility and not draw law enforcement's attention," Alvazzi del Frate said at the study's launch.

"The problem of infiltration of organised crime into legal business is a very, very serious problem," she said.

"However, despite the reduction in lethal violence, mafia groups continue to maintain extensive firearm arsenals," she warned.

Among other issues probed by the think-tank was the relationship between conflicts and illicit market prices for ammunition.

"It does seem that rising illicit market prices do reflect an expectation that the security situation is bad and is likely to deteriorate," said Small Arms Survey researcher Nicolas Florquin.

For example, prices in Lebanon for ammunition for M16 and Kalashnikov assault rifles jumped in April 2011, a month after the outbreak of the civil war in neighbouring Syria.

They then dipped slightly, before holding steady, then rising fast from November 2011 to September 2012, when the Small Arms Survey's study concluded.

"It's ammunition prices, and not Kalashnikov prices or military rifle prices generally, that tell us more about conflict dynamics, which is a better indicator of changes in local situations," said Glenn McDonald, a senior researcher at the think-tank.

"We see that ammunition prices are in fact following levels of fatality in Syria," he noted.

The study showed that the global trade in small arms is worth around €6.5 billion a year, with the illicit market making up almost half that sum.

Almost three-quarters of the globe's 875 million firearms are in civilian hands.

Approximately 526,000 people die gun-related deaths every year, but only 10 percent are on the battlefield, the study said.