Jennifer Lopez’s Argentina show was marred by a theft backstage. But the singer didn’t lose anything.The incident took place at the G.E.B.A stadium in Buenos Aires Thursday. The thief is said to have taken away a camera, a computer and a bag that contained passports of the crew, reports contactmusic.com. Lopez’s representative told News Latino that lack of security was to blame for the theft. The 42-year-old’s Argentina trip ispart of a world tour.