Two US Marines killed in Afghan base attack: official

Two US Marines were killed in an attack today on the military post in southern Afghanistan where Britain's Prince Harry is based, officials said, adding he was "not in any danger".

The attack, involving small arms and mortar or rocket fire, started around midnight local time, Master Sergeant Bob Barko of the International Security Assistance Force (ISAF) told AFP.

A defense official in Washington said the two killed were US Marines, speaking on condition of anonymity, while another US official described the attack as "complex".

Prince Harry has been deployed at the base as a military helicopter pilot. Taliban insurgents have vowed to kill him, saying earlier this week they had a "high-value plan" to attack the third in line to the British throne.

Barko said that ISAF was assessing the extent of the damage to the camp in restive Helmand province, one of the toughest battlefields in the 10-year war, but the prince was not thought to be affected.

"The information we have is that he was not in any danger," he said. The 27-year-old prince will spend four months based at the heavily fortified Camp Bastion.

In 2008, Harry was hastily withdrawn from Afghanistan when a news blackout surrounding his deployment, on the ground directing aircraft in attacks on Taliban positions, was broken.

This time, however, the military has released photographs and video of him in Afghanistan from the start.

Britain's Ministry of Defence said any risk "has been, and will continue to be, assessed".