In a gesture of good will, the Taliban movement of Afghanistan released five Iranian prisoners on Saturday, but Iranian news accounts said the move would not be enough to ease tensions that have raised the prospect of a military conflict.

A Taliban spokesman said the prisoners had been freed "as a sign of our willingness to improve relations" with Tehran. But in Iran, where tens of thousands of people turned out at nationwide protests on Friday to threaten holy war against the Taliban, the move was portrayed as inadequate.Tensions between Iran and the Taliban, the militant Islamic movement that controls most of Afghanistan, have been growing since the Taliban acknowledged that their forces killed at least eight Iranian diplomats and a journalist last month in the northern Afghan town of Mazar-i-Sharif. In response, Iran has built up its military forces along the Afghan border to what Iran says is more than 250,000 troops.

The release of Iranian prisoners was among the steps that Iran had demanded from the Taliban as a condition for averting military action. But Iranian officials said Saturday night that many more Iran-ians remained in Taliban custody, and they expressed anger at suggestions by the Taliban spokesman, Abdul Hai Mutmean, that it was time for Iran to make some gesture in return.

Taliban officials have acknowledged that they still hold at least 45 Iranian prisoners. But before any more Iranians are released, they have said, Iranian-backed rebels ought to free Taliban prisoners, and Iran should halt what they have alleged is mistreatment of some among an estimated 2 million Afghan refugees who have taken shelter in Iran during 20 years of civil war in their country.

Pakistan, one of the few countries to recognize the Taliban as Afghanistan's legitimate government, served as an intermediary in arranging the release of the Iranian prisoners who were freed Saturday.

According to Taliban officials, all had been caught driving trucks loaded with Iranian military goods when the Taliban captured Mazar-i-Sharif, which had been the headquarters of an Iranian-backed anti-Taliban militia.