The Muslim world should not accept an apology issued by U.S. President Barack Obama over the burning of Korans in an American base in Afghanistan, a top Iranian military commander said on Saturday, adding that nothing short of "burning the White House can relieve the wound of us."

Obama's Thursday apology in a letter to Afghan President Hamid Karzai sought to quell spiraling furor among Afghans, who have been protesting the act for five straight days, after Afghan workers found charred copies of the Muslim holy book on a military base near Kabul.

Open gallery view Supporters of Pakistan Tehreek-i-Insaf stand on top of a U.S. flag during an anti-American demonstration in Quetta February 25, 2012. Credit: Reuters

According to White House spokesperson Jay Carney, while the apology was "wholly appropriate given the sensitivities" about treatment of the Koran, he said Obama's primary concern was "the safety of American men and women in Afghanistan, of our military and civilian personnel there."

Responding to Obama's apology on Saturday, the commander of Iran's Basij force Brigadier General Mohammad Reza Naqd claimed that the holy book was burned by U.S. forces over the heavy slap it has been given by Islam," urging Muslims worldwide to reject the American apology.

"Nothing but burning the White House can relieve the wound of us, the Muslims, caused by the Burning of Quran in the US," he said adding: "Their apology can be accepted only by hanging their commanders; hanging their commanders means an apology," he was quoted by the semi-official Fars news agency as saying.

Naqd's comments came after, earlier Saturday, a gunman killed two American military advisers inside a heavily guarded government building in the heart of Kabul.

The Taliban claimed responsibility for the attack, saying it was retaliation for the Koran burnings, and the NATO commander recalled all international military personnel working in Afghan ministries in the capital.

U.S. officials said the assailant remained at large and a manhunt was under way.

At least 28 people have been killed and hundreds wounded since Tuesday, when it first emerged that Qurans and other religious materials had been thrown into a fire

pit used to burn garbage at Bagram Air Field, a large U.S. base north of Kabul.

Among those dead were two U.S. soldiers who were killed Thursday by one of their Afghan counterparts while a riot raged outside their base in the eastern province of Nangarhar.