Delta says it's reviewing how man boarded wrong flight. A family says he was following them

A woman says a stranger followed her family around an airport terminal and on to a Delta Air Lines plane even though he didn't have a boarding pass for the flight. Delta Air Lines said Friday it's looking into the incident, which happened earlier this month at Dulles Airport near Washington, D.C. Delta says gate agents and flight crews have ways to verify that people are allowed on to a particular flight. The airline says it's reviewing this case and has contacted airport authorities.