Dissidents claim Iran killings: A shadowy underground group says it has struck at heart of the clerical regime

WHO OR WHAT is the Babak Khoramdin Organisation, the shadowy underground group which, with increasing stridency, claims to be terrorising the leadership of Iran's Islamic regime? In little more than six months of existence, the BKO has yet failed to surface to show its face.

Only a handful of communiques - sometimes in English but more often in Farsi - provide proof of its existence. But in its latest 'operational statements', issued over the past two weeks, the BKO claims that its guerrillas have reached to the very heart of the clerical regime.

The BKO says its most important coup so far was an explosion on 17 March at the residence of Ayatollah Ali Khamenei, Iran's spiritual leader. According to its latest communique, the BKO said that, although the ayatollah escaped injury, at least five people were killed, two of them brothers of Mohammad Hussein Mousavian, Iran's ambassador to Germany.

The explosion was said to have occurred during an iftar party, marking the end of daily fasting during the holy month of Ramadan. In its reaction to the incident, which was first reported by the exiled former president, Abolhassan Bani-Sadr, the Iranian official media said rumours of the explosion stemmed from the sounds of fireworks set off to mark the start of the Iranian New Year. But according to the BKO, a powerful explosive device had been taken into the heavily guarded residence by one of the guests. He was alleged to have died under torture six days after his arrest. Despite the absence of official confirmation of the attack, Iranian newspapers have carried condolence messages addressed to Mr Mousavian on the death of his brothers.

The BKO has subsequently claimed responsibility for the assassination of Revolutionary Guard Lt-Col Mohammad Reza Fadai, one of the senior commanders in charge of state security.

As an unprecedented wave of anti-regime activities spreads alarm among the ruling mullahs, Ayatollah Ahmad Jennati, a leading cleric close to Ayatollah Khamenei, warned last Friday that 'criminal hands are out of the sleeves to kill our beloved leaders, to terrorise the Muslim people and to end the rule of Islam'.

On the basis of its communiques, the BKO appears to be a secular, nationalist group. Its coat of arms is an eclectic mix of Persian and religious symbols - an imperial lion and sword, topped with a shrine and minaret. It takes its name from the historic figure, Babak Khoramdin, who led a revolt against the Arab and Islamic domination of Persia. The group does not appear to be overtly monarchist and there are no indications that it enjoys foreign support.

Until now the main opposition group claiming to undertake armed action against the regime is the People's Mujahedin, once condemned by the late Shah as Islamic Marxists but now on increasingly friendly terms with Washington.

Iranian sources say the BKO does not aspire to mounting a coup d'etat but wants to show the clergy that it cannot ignore the will of the people. One informed estimate is that the BKO draws its strength from relatively young veterans of the Iran-Iraq war who became disillusioned during that conflict about the direction the revolution was taking.