Two soldiers with the NATO-led International Security Assistance Force (ISAF) were killed Thursday morning in a blast in restive southern Afghanistan, the ISAF forces confirmed in a statement.

"Two International Security Assistance Force service members died following an improvised explosive device (IED) attack in southern Afghanistan today," the ISAF said in the statement.

The brief statement disclosed neither the nationalities of the victims nor the details about the incident under the ISAF policy, only saying "it is ISAF policy to defer casualty identification procedures to the relevant national authorities."

Troops mainly from US, Britain and Australia have been stationed in the southern region within the framework of ISAF to curb Taliban-linked insurgency there.

Violence has been on the rise since Taliban launched an annual spring offensive on May 3.

Currently, over 130,000 NATO-led ISAF troops with majority of them Americans have been serving in Afghanistan since the Taliban regime was toppled in late 2001.

Four other ISAF soldiers were killed in similar attacks in southern and eastern part of the insurgency-hit country Wednesday.

More than 270 foreign soldiers have been killed in Afghanistan in the war against Taliban and other insurgent groups so far in 2012.