KABUL - Senior Afghan clerics said on Friday a U.S. apology for the burning of copies of the Muslim holy book at a NATO base last month would never be accepted, and demanded a trial and punishment for those who committed the "evil act."

"Those who committed this crime must be publicly tried and punished," members of a senior council of clerics said after meeting President Hamid Karzai, according to a statement issued by his office.

"The council strongly condemns this crime and inhumane, savage act by American troops by desecrating holy books of the Quran."

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Despite an apology from President Barack Obama, the desecration of the Quran at the U.S. Bagram airbase, which is being used by both U.S. and foreign forces under the NATO banner, ignited a wave of anti-Western fury across the country. Muslims consider the Koran the literal word of God and treat each book with deep reverence.

At least 30 people were killed in the protests.

The Quran burnings hurt U.S. efforts to win more trust from Afghans, an essential part of efforts to weaken the Taliban and force the militant group to negotiate an end to the war now in its eleventh year.

A string of attacks on NATO troops by Afghan security forces followed the Quran burnings, including the high-profile killing of two U.S. officers in the heavily guarded Interior Ministry.

The killing of two U.S. officers, allegedly by a police intelligence officer, in the heart of the heavily guarded Interior Ministry raised particular concern and cast fresh doubt over the effectiveness of Afghan security forces.

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If their capabilities do not improve before foreign combat troops head home at the end of 2014, the country could face prolonged instability.

An Afghan government commission investigating abuse accusations at the largest U.S. jail in Afghanistan, which is at the Bagram site, has said inmates had reported being tortured and being held without evidence.

Control over Afghans captured by U.S. forces is a major stumbling block in negotiations between Kabul and Washington on a strategic partnership agreement. NATO's night-time raids on Afghan homes, which Karzai objects to, are another point of contention.
Reuters and msnbc.com staff contributed to this report.

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An investigation into the burning of copies of the Quran at a NATO base in Afghanistan, which sparked deadly protests, could be concluded as early as Thursday, senior military officials said Wednesday.

Seven people were killed in clashes between Afghan security forces and demonstrators across Afghanistan who were angry at the burning of Muslim holy books.

The demonstrations prompted the U.S. to lock down its embassy and bar its staff from traveling.

The burning incident tapped into anti-foreign sentiment fueled by a popular perception that foreign troops disrespect Afghan culture and Islam.

NATO apologized Tuesday for the burning of the books, which had been pulled from the shelves of the Parwan Detention Facility, adjoining Bagram Air Field.

A spokesman for ISAF, the US-led international forces in Afghanistan, said it is still unclear why several Qurans sent to a burn pit for disposal or who gave the orders.

German Gen. Karsten Jacobsen said an ISAF investigation is already under way to determine why and who gave the order to gather up the materials for disposal, and if there was any misconduct those responsible would be held accountable.

Jacobsen offered however that it appears those who gave the order may have been unaware that the Korans and other religious materials were included in the material marked for disposal. 

Jacobsen said early reports have not been confirmed that prisoners at the detention facility in Parwan were writing in the Qurans and using the Qurans to pass extremist and inflammatory messages to other prisoners.

Jacobsen added however that "even if that were true, it would not change the violent situation in the streets."

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He said the Qurans were included in a considerable amount of material sent to the pit for routine burning, and were discovered by local Afghan workers. One of the Afghan laborers burned his hands retrieving the Qurans from the flames.

Jacobsen said that ISAF hopes to release the preliminary results of its investigation by Thursday morning.  "The objective is to be as visible and transparent as possible to try to calm the situation" and prevent further violence, he said.

The Afghan Interior Ministry earlier said in a statement that clashes during a protest in the eastern province of Parwan left four people dead. It said an investigation was under way to determine what happened.

The other deaths occurred at a U.S. base outside Kabul, where security guards killed one person, and in Jalalabad and Logar province, the ministry said.

The demonstration in Kabul drew thousands of protesters, who chanted "Death to America," hurled rocks and set tires alight outside a complex that is home to foreign contractors, police and some coalition military forces.

PhotoBlog: Protests spread amid Afghan fury at Quran burning

Nearby, angry demonstrators set a fuel truck ablaze on a main highway running east out of the city, sending black smoke billowing into the air.

In Tuesday's apology, U.S. Gen. John Allen, the top commander of American and NATO forces in Afghanistan, said the burning was an inadvertent error. "It was not a decision that was made with respect to the faith of Islam," he said. "It was a mistake. It was an error. The moment we found out about it we immediately stopped and we intervened."

Jim Miklaszewski, NBC News chief Pentagon correspondent, The Associated Press, Reuters and msnbc.com staff contributed to this report.

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