Tehran: Bells chimed across Iran on Monday to mark the return from exile in 1979 of Ayatollah Ruhollah Khomeini, the trigger for a revolution which spawned an Islamic state now engulfed in a deep political crisis.
To mark Khomeini`s triumphant return after 15 years in exile, all schools, trains and boats rang their bells at precisely 9:33 am (0603 GMT), the moment his plane touched down at Tehran`s Mehrabad airport on February 1, 1979.
President Mahmoud Ahmadinejad and other senior Iranian officials paid homage to the cleric at his mausoleum in southern Tehran.
Monday marked the start of 10 days of celebrations which culminate on February 11, the 31st anniversary of the fall of the US-backed shah who had ruled the country for nearly four decades but who fled two weeks before Khomeini`s return.
On his arrival on board an Air France jet 31 years ago, the bearded Khomeini, then 76, had vowed to establish a new government in Iran.
"I will appoint a government. I will slap this government on the mouth," he said in an address at Tehran`s Behesht Zahra cemetery, referring to the government of the shah`s last prime minister Shahpour Bakhtiar.
The charismatic cleric assumed the role of Iran`s supreme leader, which he held until his death in 1989.
During his conservative rule, Iran became embroiled in a brutal conflict with Saddam Hussein`s neighbouring Iraq. Over a million people were killed on both sides during the war.
Khomeini had also backed Islamist students who stormed the US embassy in Tehran in November 1979 and took its personnel hostage for 444 days, prompting Washington to severe ties with the Islamic republic.
Khomeini branded the United States as the "Great Satan" and diplomatic ties were severed.
Relations between Iran and the US have deteriorated further during the rule of hardliner Ahmadinejad, who was controversially elected for a second term last June in an election the opposition claims was massively rigged.
Tension has also peaked between Iran and the West over Tehran`s nuclear programme, which world powers believe is masking an atomic weapons programme despite repeated assertions to the contrary by Iranian leaders.
"I am sure the Iranian people will do something on February 11, which will disappoint the enemies and the tyrants completely," Ahmadinejad said in a short address at the mausoleum.
"This year will see the definite failure of capitalism, inhuman liberalism and the start of globalisation of the Islamic revolution."
In a keynote speech at a ceremony at Behesht Zahra cemetery mostly attended by military officials, lawmaker Gholam Ali Haddad Adel insisted that Iranians "are sticking to the commitment made 31 years ago."
"They (Iranians) are telling the tyrants that they are moving full steam ahead to defend the revolution," Haddad Adel said as the crowd chanted "Death to America! Death to Israel!"
Ahmadinejad`s June 12 re-election triggered one of the worst political crises in the history of the Islamic republic.
Some of the early pillars of the regime such as Mir Hossein Mousavi, who was prime minister under Khomeini, and Mehdi Karroubi have turned into its bitter opponents, accusing the authorities of "fraudulently" re-electing Ahmadinejad.
The opposition movement, backed by powerful figures such as ex-presidents Akbar Hashemi Rafsanjani and Mohammad Khatami, has shaken the pillars of the regime and bitterly divided the nation`s clergy.
Violent clashes since the June election between opposition supporters and security forces have killed dozens, wounded hundreds and seen thousands of arrests.
Hundreds of protesters have been put on trial on charges of threatening national security and attempting to topple the regime.
Iranian authorities have warned that they will crack down on protesters if they attempt to stage another anti-government demonstration on February 11, when traditionally hundreds of thousands of Iranians take to the streets in celebration.
Mousavi and Karroubi have implicitly called on their supporters to demonstrate on the anniversary of the revolution, Karroubi`s website Sahamnews.org said on Saturday.