WASHINGTON: A mysterious affliction dubbed “Havana Syndrome” that has brought severe headaches, nausea and possible brain damage to US diplomats has many officials convinced they are under sustained attack using electronic weapons.

On Tuesday, US Vice President Kamala Harris delayed for several hours a trip to Vietnam after the US embassy in Hanoi reported a possible case involving “acoustic incidents” there, raising concern she could be a target. Ultimately Harris did go to Hanoi, and the State Department said it was investigating a case of what the US government officially dubs an “anomalous health incident” or AHI. It was the most recent of dozens of such cases reported by US diplomats and intelligence officers since 2016.