The Liberals' foreign affairs critic says he can't understand why the government wants to keep secret the number of Afghan detainees captured by Canadian forces when the U.S. military regularly makes public the same information.

Ujjal Dosanjh made the comments while speaking to a joint meeting of two parliamentary committees on Wednesday after Defence Minister Gordon O'Connor refused to divulge any numbers, citing troop safety.

The Taliban could use such information for propaganda purposes and to plan attacks against Canadian forces, O'Connor told the committees on national defence, and foreign affairs and international development.

Since the beginning of May, the U.S. military has issued 25 media releases detailing the capture of at least 100 Afghan prisoners.

The information is posted on a U.S. army website, with details of the captures, including where they occurred, the number and type of weapons seized, and information about the prisoners, such as rank, and sometimes even names.

Dosanjh wondered why Canadian officials don't follow the U.S. lead.

"Obviously they're our allies and friends and we work with them, yet we, this government of Canada, is not prepared to release the same information to Canadians."

While O'Connor remained tight-lipped about numbers, Public Safety Minister Stockwell Day was forthcoming about the number of detainees who've made claims of abuse at the hands of their Afghan jailers.

Day told the two-hour meeting that four prisoners have complained of mistreatment since they were captured by Canadian forces in Afghanistan. The minister revealed news of the first two cases of alleged abuse in April.

Foreign Affairs Minister Peter MacKay told the meeting the complaints were made after Canada signed a new prison-monitoring agreement last month. The complaints point to the effectiveness of the system, he said.

New monitoring deal 'is working'

"They were received directly by Canadian officials during visits that were arranged that we have sought and were received," he said. "While these allegations are serious, it is proof that the enhanced arrangement is working."

Both MacKay and Day cautioned that Taliban fighters are trained to claim they have been tortured if they end up in detention.

The new arrangement, announced as a cure to the controversy surrounding Canada's policy of transferring detainees to Afghan jailers, allows access to all detainees captured by Canadian soldiers for as long as they are imprisoned.

Dosanjh said the fact these new allegations have arisen proves the latest monitoring arrangement isn't working.

"These ministers, the bunch that were here today, they believe that in Afghanistan if you take detainees, we should be able to treat them differently — less than we would be able to treat someone else, and that is absolutely despicable, as a Canadian, for me."

MacKay said Canadian officials learned of the new allegations after making five visits to Afghan jails, and have notified the Afghan Independent Human Rights Commission and the Red Cross to investigate.

Both he and Day said Canadian officials have seen no physical signs of abuse and heard no evidence to verify the claims.