Iran politicians go on trial

By CNN correspondent Kasra Naji

TEHRAN, Iran (CNN) -- More than 30 Iranian opposition politicians have gone on trial behind closed doors, an event that human rights supporters said was timed to embarrass Iran's reformist president.

The group, many of them veteran liberal politicians, have been charged with acting against the country's national security and planning to overthrow the regime.

Authorities did not announce the exact number of people being tried.

The trial was being held on Sunday at Tehran's Islamic Revolutionary Court, which said in a statement that the security nature of the charges required the trial to be held in camera, or behind closed doors.

All those on trial were arrested in May and April, and though some were released on bail, others remain in detention.

The human rights organisation Human Rights Watch has called on the Iranian authorities to release all those charged, saying the accused have committed no crimes other than to exercise their basic human rights to meet peacefully and express themselves freely.

Human Rights Watch said those on trial are pawns in the power struggle between Iranian reformists and the conservative clerics who still control the judiciary.

The group also said the timing of the trial was calculated to cause maximum embarrassment to President Mohammad Khatami, currently in New York to attend the United Nations General Assembly.