After immigration agents detained two Iraqis on Saturday at New York's John F. Kennedy International Airport, their lawyers and two U.S. representatives accompanying them tried to cross into a secure area — and were stopped themselves.

"Step back! Step back!" the agents shouted at them.

A few minutes later, Heidi Nassauer, chief of passenger operations for U.S. Customs and Border Protection (CBP) at the airport, was called over.