US authorities were under pressure yesterday to explain how a mentally ill man, whom his family said “changed” after serving in Iraq, was able to arm himself and shoot five people dead in Fort Lauderdale airport. Runaway chaos: People stand on the tarmac at Fort Lauderdale-Hollywood International Airport last Friday after a gunman opened fire inside the terminal Photo: AP Photo/Lynne Sladky US authorities were under pressure yesterday to explain how a mentally ill man, whom his family said “changed” after serving in Iraq, was able to arm himself and shoot five people dead in Fort Lauderdale airport.