BEIRUT, AUG. 6 -- About 50 pilgrims returning to the Lebanese capital today from their travels to Mecca said they heard shots fired and saw people trampled to death in the first independent testimony of last week's riots that killed more than 400 outside the Grand Mosque of Islam's holiest city.

The pilgrims, some still clothed in the traditional white robes of the pilgrimage, or hajj, appeared tired and were reluctant to talk to reporters. The usual throng of well-wishers, who normally greet the returning pilgrims with flowers, palm branches and banners, were absent this year at Beirut International Airport.

"There was rioting. We heard the sound of shots. Fistfights and beating broke out. Many innocent people were trampled to death" when the mob started to flee, said one traveller, who gave his name only as Abu Ali. According to the official Saudi version of the riots, no shots were fired in the clash that has stirred Arab-Persian animosity. The Saudis claim the violence was perpetrated by Iranian protesters who attacked police and crushed other pilgrims in a stampede.

Another pilgrim in his forties who declined to be identified said: "There were demonstrations and then there was a showdown between Saudi police and Iranians. We heard shooting."

{In Washington, Saudi Ambassador to the United States Prince Bandar bin Sultan yesterday reiterated the Saudi claim. "I can assure you that not a bullet was fired. If it had been, we would not have had 85 casualties," Sultan told a news conference.

{In Saudi Arabia, authorities said the government still did not know the whereabouts of four diplomats who were kidnaped last weekend in Tehran. Mobs in Iran's capital stormed both the Saudi and Kuwaiti embassies last Saturday after the riots in Mecca.}

Meanwhile, a previously unknown organization calling itself The Sons of Hezbollah -- The Hejaz Branch delivered a package of statements and photographs to foreign news agencies which it said were distributed among Shiite worshippers in Saudi Arabia. Hejaz, the western province of Saudi Arabia in which Mecca and Medina are located, is predominantly Sunni Moslem, as is most of the Arab world. A poster in the package pictured five people who, according to dates given, have died in Saudi Arabia during the hajj season. Writing at the bottom of the poster indicated it was printed in the Iranian city of Qum for distribution in Saudi Arabia. The accompanying statement claimed the five were killed by the Saudi regime and called them the "Hejaz martyrs."

One of the statements claimed Saudi authorities were repressing Shiite worshippers in Dammam by closing down their mosques and shutting off water and electricity from husseiniyas, meeting and prayer places for religious Shiite Moslems. The Shiite minority in Saudi Arabia is concentrated in the towns of Dammam, Dhahran, Al Ghasim, Al Hasa and Sihat in the eastern province.

The statement also claimed that the Saudi monarch, King Fahd, ordered the closure of the large Shiite mosque in the Dammam region as well as other husseiniyas and a mosque in the town of Sihat last Thursday, and that the imam leading Friday prayer in Dammam and his flock were warned not to go through with their prayers.