Updated

WASHINGTON -- A report being released Monday by a mayors group finds that nearly half of the guns that crossed state lines and were used in crimes in 2009 were sold in just 10 states.

Those states accounted for nearly 21,000 guns connected to crimes in other states, says the survey by Mayors Against Illegal Guns, an association of more than 500 mayors led by New York's Michael Bloomberg and Boston's Thomas Menino.

The Bureau of Alcohol, Tobacco, Firearms and Explosives traced more than 145,000 guns used in crimes in 2009 and found that more than 43,000 guns were sold in other states.

Forty-nine percent of those guns were sold in Georgia, Florida, Virginia, Texas, Indiana, Ohio, Pennsylvania, North Carolina, California or Arizona.