WELLINGTON - New Zealand Prime Minister John Key expressed his sorrow Monday at the news that another three soldiers had died in Afghanistan, bringing the total number of New Zealand soldiers killed in Afghanistan to 10.

Key said the latest deaths underscored the gravity of the situations New Zealand soldiers faced daily in Afghanistan.

"The three brave soldiers paid the ultimate price for their selfless work, and my thoughts are with their families and friends as they mourn their loved ones," Key said in a statement.

The three members of the Provincial Reconstruction Team in Bamyan province were killed by a roadside bomb, the New Zealand Defense Force announced early Monday.

They died when an improvised explosive device exploded at about 9:20 am Afghanistan time on Sunday, said a statement from the NZDF.

The troops were traveling in the last vehicle in a convoy when it was hit by the blast. The remaining personnel in the patrol secured the location and waited for support, said the statement.

Two other New Zealand soldiers in the provincial reconstruction team died on Aug 4 in an attack by insurgents.

"We are deeply saddened by this loss, especially given the recent incident on Aug 4," Chief of the New Zealand Defense Force, Lieutenant General Rhys Jones, said in the statement.

"On behalf of the entire New Zealand Defense Force, I extend my deepest sympathies to the families, colleagues and friends of the personnel involved," said Jones.

Defense Minister Jonathan Coleman said the deaths would come as a deep shock to the nation.

The government was still receiving details of the incident and would make more information available at a press conference later Monday, he said.