Two US Marines were killed and other Americans were wounded on Friday during a Taliban attack on a base in southern Afghanistan where Britain's Prince Harry is stationed, US officials told Reuters, speaking on condition of anonymity.
A spokesman for Nato-led forces in Afghanistan said Harry was on the base at the time of the attack but was unharmed.
"Prince Harry was never in any danger," spokesman Martyn Crighton said, adding that the Nato-led International Security Assistance Force (ISAF) would investigate whether his presence on the base had motivated the attack.
The attack involved rocket-propelled grenades, mortars and small-arms fire, with insurgents breaching the perimeter of Camp Bastion in volatile Helmand province, US officials said.
Crighton declined to offer that level of detail or give the nationalities of the victims. Crighton also did not say precisely how many people were wounded in the attack.
Earlier this week, the Afghan Taliban said they were doing everything in their power to either kill or kidnap Queen Elizabeth's grandson in what they dubbed their "Harry Operations."
Crighton said ISAF would investigate whether his presence on the base had motivated the attack.
A US official told Reuters that an initial report estimated five Americans were wounded but added that the extent of their injuries was unclear. The official said that this was only an initial report and that the number could change.
Crighton said the attack took place between 9 pm and midnight on Friday and that Nato-led forces were still securing the area in and around Camp Bastion.