The United Nations (search) Sunday condemned as "utterly unacceptable" the alleged abuse of detainees at the main U.S. base in Afghanistan and called on the American military to allow an investigation by Afghan human rights officials.

The world body was responding to a New York Times article Friday reporting that poorly trained U.S. soldiers had repeatedly abused detainees. Afghan President Hamid Karzai (search) on Saturday called for tough punishment for the abusers, and for the United States to hand over all Afghans still in its custody.

The report cited a 2,000-page confidential file on the Army's criminal investigation into the deaths of two Afghans at the Bagram base north of the capital, Kabul, in December 2002.

"Such abuses are utterly unacceptable and an affront to everything the international community stands for," said Richard Provencher, spokesman for the United Nations in Afghanistan (search). "The gravity of these abuses calls for the punishment of all those involved in such inexcusable crimes."

He said all detainees should be treated in accordance with international law and called for "firm guarantees" that such abuses would not be repeated.

Provencher said the U.S.-led coalition should permit investigators from the Afghan Independent Human Rights Commission to have access to detainees and be allowed to monitor their cases.

The U.S. military did not immediately respond to requests for comment Sunday, but has earlier responded to the Times report by saying no incidents of abuse would be tolerated.

Provencher said the United Nations "will redouble" its own efforts to follow up on complaints regarding the abuse of detainees.

Speaking to reporters on Saturday before a visit to the United States, Karzai also demanded more say over operations by the 16,700 U.S. troops still in the country, including an end to raids on the homes of Afghans unless his government was notified beforehand.

Afghan Defense Ministry spokesman Gen. Mohammed Zaher Azimi reiterated the demands Sunday.

"No operations in the future should be done without the cooperation of the Afghan government," he told reporters. "If anyone has to be arrested, it should be Afghan authorities who arrest them. These are the demands of the Afghan government."

Karzai — seen by his critics as an American puppet — issued his tough statement after the reports of prisoner abuse by American forces at Bagram, and anti-U.S. riots that broke out across the country earlier this month, leaving at least 15 people dead.

The unrest was triggered by a Newsweek magazine report, later retracted, that the Quran was defiled by interrogators at the U.S. prison at Guantanamo Bay, Cuba, and likely further fueled by long-standing complaints of heavy-handed search operations and the deaths of civilians in U.S. operations in Afghanistan.

In Washington, White House spokesman Trent Duffy said the president was "alarmed by the reports of prisoner abuse," and wants them thoroughly investigated. Duffy said seven people were being investigated about abuse at Bagram.

The Times' allegations of maltreatment were supported by Human Rights Watch, a New York-based watchdog, which said that at least six detainees in U.S. custody in Afghanistan have been killed since 2002.

In December, Pentagon officials said that eight deaths of detainees in Afghanistan — including the two mentioned in the Times report — had been investigated since mid-2002. Hundreds of people were detained during and after the campaign by U.S.-led forces to oust the hardline Taliban regime in late 2001.

After the outcry over abuse at the Abu Ghraib prison in Iraq, the military also initiated a review of its detention facilities in Afghanistan and later said it had modified some of its procedures, although the review's findings have not been made public.