OTTAWA — Canadian troops handed Afghan detainees to local authorities in the knowledge they would be tortured, and later tried to silence critics of the practice, a senior Ottawa diplomat told lawmakers.

"According to our information, the likelihood is that all the Afghans we handed over were tortured," Richard Colvin, former number two at the Canadian embassy in Kabul told a parliamentary committee probing allegations of torture.

He said most of the detainees were not "high-level targets" or even Taliban, but wrongly-detained peasants and farmers.

"In other words, we detained, and handed over for severe torture, a lot of innocent people," he testified.

Colvin also claimed his warnings, first delivered in spring 2006, were ignored by senior military commanders and government officials until prisoner mistreatment allegations were reported in the media a year later.

After that, he said, diplomats were instructed by top members of the foreign affairs department not to keep written records of discussions of torture allegations.

Colvin worked for Canada's Foreign Affairs department in Kandahar in 2006 and was later promoted to second-in-command at the Canadian embassy in Kabul until late 2007.

In both jobs, he visited detainees transferred by Canadian soldiers to Afghan prisons and reported his findings to Ottawa.

The Canadian government, which has thousands of troops in Afghanistan, has denied there is any firm evidence that detainees transferred by its officials were indeed tortured.