U.S. Defense Secretary Leon Panetta on Tuesday rendered his apology for the alleged burning of Islamic religious materials including copies of the Quran at a military base in Afghanistan.

U.S. Defense Secretary Leon Panetta [File photo]

In a written statement, Panetta said Marine Corps Gen. John Allen, commander of the NATO-led International Security Assistance Force (ISAF) in Afghanistan, had notified him of "the deeply unfortunate incident."

"He and I apologize to the Afghan people and disapprove of such conduct in the strongest possible terms," the secretary said. " These actions do not represent the views of the United States military. We honor and respect the religious practices of the Afghan people, without exception."

"I will carefully review the final results of the investigation to ensure that we take all steps necessary and appropriate so that this never happens again," he added.

Thousands of Afghans rallied on Tuesday against the alleged burning of Qurans and other Islamic religious materials during trash disposal at the Bagram Airbase, the main U.S. military center in Afghanistan.

In a separate statement, Allen apologized for the alleged misconduct and ordered an investigation.

"I offer my sincere apologies for any offense this may have caused," the U.S. general said. "I have ordered an investigation into a report I received during the night that ISAF personnel at the Bagram Airbase improperly disposed of a large number of Islamic religious materials which included Qurans."