TEHRAN, Feb 1: School bells rang and helicopters showered flowers on the tomb of Ayatollah Ruhollah Khomeini as Iran marked the 20th anniversary of the Islamic leader's return from exile, reports AP.

The bells — along with whistles। from trains and ships at port — were sounded at 9:33 am (0603 GMT), the moment Khomeini's jet touched down at Tehran's Mehrabad Airport on February 1. 1979.

Helicopters showered the route Khomeini travelled to make his first speech at the Be-hesht-e-Zahra cemetery. They also dropped flowers on his golden-domes tomb inside the sprawling graveyard south of Tehran.

After Khomeini returned from 15 years of exile, he overthrew the US-supported Shah and proclaimed an Islamic Republic in Iran.

His actions shocked the United States and raised fears across the Arab world that Khomeini would follow through on his pledge to export his strict vision of Islam.

Shortly after Khomeini's rise to power, Iranian students stormed the US embassy in Tehran and seized 52 American diplomats. who were held hostage the capital for more . than a year.

On Monday, thousands gathered inside the shrine — aglow with lights from giant chandeliers and adorned with precious Persian carpets — to pay tribute to Khomeini.

State-run television broadcast live from the shrine, where Khomeini’s grandson. Hassan, said his grandfather had "come as a hero and left as a hero."

Hashemi Rafsanjani, Iran's former president who now heads a powerful policy-making body, told the crowds that the United States was still the enemy.

He claimed that only Iran's military might prevented the United States and Britain from carrying out attacks on Iran

similaF to those against Iraq.

"If we did not have this military and defensive strength, we would be a delicious morsel for America." Rafsanjani said.

He claimed Iran was self-sufficient in arms, building every-tliing from "Colt bullets to intercontinental missiles, tanks, shells, mortar-launchers, radars and communication systems."

Earlier, President Mohammad Khatami and Ayatollah Ali Khameini. Khomeini's successor as Iran's supreme leader, paid their respects at the shrine.