Public security

Homeland Security report cited lone offenders as threat to large events in the South, weeks before Las Vegas massacre

Less than two weeks before the Las Vegas mass shooting, law enforcement officials warned that "unaffiliated lone offenders" were one of the biggest threats to large gatherings in the southern U.S., according to a confidential report obtained by CNBC.

Las Vegas was not cited as an area of focus by this report, which instead noted concerns around the South-Central region in states such as Texas and Oklahoma.

Upcoming large public events in the southern U.S. listed in the report included marathons, festivals, fairs, Thanksgiving Day parades, the March Madness Final Four, and the South by Southwest festival.