Firearm ownership in Finland is the third highest per capita in the world, according to a new international survey.

The Small Arms Survey 2007 by the Geneva-based Graduate Institute of International Studies says that there are 56 guns for every 100 residents in the country.

On a per-capita basis, the United States has the world's most heavily armed citizenry, with 90 guns per 100 people, followed by Yemen with 61 per 100 people, and then Finland.

The study says that civilians hold around 650 million handguns worldwide, 40 percent of them in the United States.

Other countries with high per capita levels of private firearms are Switzerland (46), Iraq (39), Canada (31), Sweden (31) and Germany (30).

According to researchers, gun violence often occurs in places undergoing rapid urban growth, and when lawless areas are created by extreme poverty and the absence of effective policing.