A computer system glitch has caused big delays at customs and border control at US airports.<br /><br /> In cities including Miami, Los Angeles, Boston, New York and Atlanta, there were long lines of travellers affected.<br /><br /> The glitch lasted several hours but is not thought to have been caused by anything suspicious.<br /><br /> One traveller in Boston said: “It looked like the machines were broken, the green cards weren’t working. It was a mess in there. <br /><br /> “I don’t know, it took forever, an hour and a half maybe to get through the whole thing. I’m ready to go home.”<br /><br /> The delays came at the worst time of the year, as people return from holiday breaks.<br /><br /> All airports were declared back on line after about four hours. <br /><br /> Officials say during the disruption people were still screened according to strict security standards.<br />
