ISLAMABAD, Pakistan - An independent Pakistani commission investigating the U.S. raid that killed Osama bin Laden has ordered the government to prevent the al Qaeda chief's wives and children from leaving Pakistan without its permission.

Three of bin Laden's wives and several children have been detained since the May 2 American raid on the terror leader's compound in the northwest Pakistani garrison city of Abbottabad. In recent days, Pakistani authorities indicated they were about to send the youngest wife to her native country, Yemen.

The commission's order, which was issued late Tuesday and is supposed to be binding, was directed in part at Pakistan's powerful Inter-Services Intelligence spy agency, which tends to operate beyond civilian control and is believed to be holding the family.

It wasn't clear if the powerful security agencies would heed the order.

Past Pakistani commissions and inquiries into other issues have accomplished little or seen their findings never published. But the so-called Abbottabad commission appeared to be seeking to take advantage of unusual public pressure on the security establishment since the controversial raid.

The ability of the U.S. to carry out the operation unilaterally infuriated Pakistanis who saw it as a violation of their country's sovereignty. At the same time, U.S. lawmakers were outraged to learn that bin Laden had managed to hide, apparently for years, in a city that is home to a top Pakistani military academy.

The al Qaeda leader's discovery has raised suspicions that elements of Pakistan's armed forces or intelligence services aided bin Laden, but U.S. officials have said they've seen no evidence that Pakistan's top civilian or military leaders knew of his whereabouts.

Since the raid, Pakistani commentators and lawmakers have been unusually vocal in their criticism of the military -- always a risk in a country where the security establishment has a history of staging coups and is routinely accused of making its foes disappear.

Even pro-military commentators have demanded to know why the army was unaware of the U.S. intrusion until after it ended.

At first, it appeared the government was willing to let the army handle the inquiry into the bin Laden raid on its own. But opposition leaders and others demanded an independent commission that included nonmilitary representatives, and the government eventually agreed.

The panel is headed by a Supreme Court justice, but it also includes a retired general and representatives from the police and diplomatic community.

The commission is charged with investigating how bin Laden managed to hide in Abbottabad for so long, and the circumstances surrounding the U.S. operation. Its first meeting, held Tuesday, was not open to the public or the press.

According to a statement late Tuesday, the group promised a thorough and independent investigation. It said it would call upon senior civilian and military leaders to attend proceedings if necessary, and encouraged members of the public who had information to contact it.

"Their identity will be kept confidential and they will also be legally protected," its statement added.