Alleged abuse of prisoners -- including three deaths -- at U.S. jails in Afghanistan (search) has prompted "very significant changes" in how the military treats detainees, including quicker transfers from jails at outlying bases, a U.S. general said Tuesday.

But Lt. Gen. David Barno rejected demands by an Afghan human rights group for access to the prisoners to make sure they are not suffering the same abuses that have come to light in Iraq (search).

Speaking to reporters, Barno said the military had looked into "challenges and problems" at holding facilities in Afghanistan. He didn't say what the allegations were, or if any of them had proved true.

"One of the things we've done recently is to reduce the amount of time we're allowing local [American] commanders to have people in their temporary facilities before they come to Bagram," the main U.S. base north of Kabul (search), Barno said.

Barno was fielding questions about reported complaints by former detainees at bases including Gardez in eastern Afghanistan and Kandahar, in the south.

He said all complaints were investigated and "appropriate action" taken as a result.

"I am aware of a number of the allegations out there. We have run a series of investigations on some of the challenges and problems that have been brought up with some of the remote holding facilities," he said.

Sima Samar, head of the Afghan Independent Human Rights Commission, said detainees' relatives were outraged by the images of abused prisoners in Iraq.

Samar said she sent a letter to Barno and President Hamid Karzai asking for access to the prisoners. "We don't want the same things happening to Afghans."

But Barno said the military had no plans to let anyone other than the International Committee of the Red Cross visit prisoners.

"We feel they provide a more-than-sufficient ... unbiased, unfiltered look at our procedures," Barno said. "I think they represent the interests of the persons under control quite well."

Samar said she had received about 40 complaints this year, mainly about prisoners' lack of contact with their families and U.S. troops breaking down doors to search homes. None alleged physical abuse, she said.

The military opened a formal investigation into the deaths of two Afghans at Bagram's closely guarded jail in December 2002, but says it has had trouble gathering evidence and has yet to release results.

Military autopsies found that both men died of blunt force injuries.

A third Afghan died last June at a holding facility in eastern Kunar province.

A U.S. intelligence official said last week that the CIA inspector general is investigating that death because it involved an independent contractor working for the agency.

Barno said "a number of very significant changes" were made at Bagram as a result of the deaths there, but the military refuses to give details of its prison regime.

Barno said he was now "very confident in our procedures."

The U.S. military views Taliban and Al Qaeda prisoners as "unlawful combatants," and has held hundreds captured in the war that ousted the Taliban in late 2001 for more than two years without formal charge or access to lawyers.

In their latest operations, U.S. forces detained 13 suspects Saturday in Zabul province, near the Pakistani border, where resurgent Taliban militants have carried out a string of attacks on Afghan forces. It hasn't said where they were taken.

Afghan government officials have expressed concern that any sign of widespread abuse could turn ordinary Afghans against the presence of foreign soldiers, but remain supportive of the presence of 20,000 U.S.-led troops here.

The United States is relying also on Pakistan to help it crush militants, and Barno on Tuesday dropped criticism of Islamabad's resolve to move against insurgents on its side of the border.

Islamabad has offered amnesty to foreign militants on its side of the border if they agree to register with authorities and live in peace. A deadline for foreign fugitives to accept or face possible military action expired Monday.

But after talks with Pakistani military leaders in Pakistan on Monday, Barno said Islamabad had "complementary military-political plans to kill, capture or ensure the surrender of these dangerous elements."

"I have confidence in the direction they intend to pursue," Barno said.