"Your walking alone, a group of people are hanging out just ahead. Suddenly they surround you. Before you know it you're being robbed. It's called a pack robbery, a robbery involving a group of assailants and it can be violent. In times like these trust your instincts. Don't become their next victim. Avoid suspicions groups, avoid desolate or poorly lighted areas, be aware of your surroundings. To learn more about pack robberies visit NCPC.Org or contact your local enforcement agency. A message from the US Department of Justice, National Crime Prevention Council and the Ad Council."
This is an add that talks about pack robberies.