South Carolina ? Ten states are responsible for the bulk of illegal guns that are shipped across state lines for use in crimes, according to a report released Friday by a national coalition of mayors.

About 30 percent of guns traced by federal agents in 2006 and 2007 during crime investigations were bought in a state other than where the crime occurred, said the report by Mayors Against Illegal Guns, which largely blamed the transport of illegal guns on states with lax gun laws.

For 2007, the top sources for guns used in crimes elsewhere were Georgia, Florida, Texas, Virginia, California, Ohio, North Carolina, Indiana, Pennsylvania and Alabama.

However, the report’s authors placed greater emphasis on per-capita exports of guns, saying that data is a better indicator of lax gun laws. The gun-friendly South accounted for a disproportionate amount of the problem when population size was factored in, according to the report.

West Virginia is the top exporter, per capita, of illegal guns, with 41 traced guns per 100,000 state residents, followed by Mississippi, at 39 guns per 100,000, and South Carolina, at 31. The average national rate is 11 exported guns.