Assassinated prime minister Indira Gandhi was consigned to the flames of a Hindu funeral pyre today as a grieving India reeled from four days of sectarian violence that ranked among the worst since independence was won 37 years ago.

As hundreds of thousands of followers strained for a glimpse of the cremation and millions more watched on television, Gandhi's son and her successor to the leadership of the world's largest democracy, Rajiv, walked around the funeral pyre seven times with a flaming torch in his hand and turned the sandalwood bier into a sheet of fire.

A three-volley rifle salute reverberated across the Yamuna River basin near the place where Mohandas K. Gandhi, who led India to freedom from British rule, and the slain prime minister's father, Jawaharlal Nehru, who was India's first prime minister, also were cremated.

As Brahman pundits (those learned in Sanskrit and Hindu philosophy) chanted Vedic hymns and family members climbed the 10-foot-high platform to heap wooden logs atop the slowly smoking pyre, a collective moan of grief arose from thousands of mourners, followed abruptly by stillness as orange tongues of flames leaped higher.

"From elements you come, to elements you return," Hindu priests chanted in Sanskrit as official mourners circled the pyre and fed the flames with sandalwood dust and cups of ghee (clarified flammable butter).

The tranquility of the cremation spectacle was offset only partially by the presence of thousands of infantry soldiers and armed paramilitary security forces around the pyre and the approaches to it, vividly underscoring the fear of Hindu-Sikh violence that kept many mourners from attending the funeral.

While the government claimed to have brought under control the mob rampages against Sikhs over the killing of Gandhi on Wednesday by two Sikh security guards, arsonists turned a predominantly Sikh south Delhi truckers' neighborhood into an inferno of blazing trucks this morning.

There were widespread reports of other clashes as the unofficial death toll in New Delhi alone rose to more than 400. At least 700 people are believed to have been killed throughout the country, although the government has issued no official figures for fear of inflaming communal passions. United News of India estimated the death toll during four days of violence to be 900, and The Associated Press put the figure at more than 1,000.

Indian news agencies reported tonight that about 100 towns still were under curfew, 38 of them in the central state of Madhya Pradesh, which has experienced the worst violence in the past three days. Troops have been deployed in 28 towns or cities.

Seven infantry brigades of the Army, consisting of 21,000 soldiers and an equal number of backup personnel, were deployed in New Delhi today to maintain order.

The AP, quoting Indian news agencies, reported that the curfew around New Delhi was being relaxed Saturday and that the government was airlifting troops from the south of India to reinforce security in the capital.

There was no evidence of violence during the funeral and during the 3 1/2-hour procession in which Gandhi's body was borne six miles atop a gun carriage from her former family home to the cremation site.

Several hundred thousand mourners watched the cortege wind its way to the banks of the Yamuna, but the crowds were much smaller than the 1 million to 2 million expected when funeral preparations were made. Crowd estimates ranged from 300,000 to nearly 1 million.

Continuing daylight curfews in some outlaying areas, fear by many New Delhi residents of renewed mob violence and a public transportation system paralyzed by the absence of the Sikhs who, for the most part, control it, were given as the reasons for the unexpectedly low turnout.

Leaders representing 100 nations, including 14 presidents, attended the funeral. Britain and the Soviet Union were represented by their prime ministers, Margaret Thatcher and Nikolai Tikhonov, respectively, and the United States by Secretary of State George P. Shultz and four former U.S. ambassadors to India. Three of India's neighbors, Pakistan, Bangladesh and Sri Lanka, were represented by their presidents.

Shultz and Tikhonov met at the Soviet Embassy here for 30 minutes and, according to Indian news agencies, discussed the international situation.

Shultz had an hour-long meeting with Pakistani President Mohammed Zia ul-Haq at a hotel, and they are understood to have discussed the situation in South Asia. Zia apprised Shultz of his meeting with Rajiv Gandhi.

Four hours before the funeral, Shultz met with Rajiv Gandhi briefly at 1 Safdarjang Road, Indira Gandhi's residence and office. The secretary invited the new Indian leader to visit Washington early next year, but no date was set.

Escorted by an honor guard of 175 soldiers and airmen, the flower-bedecked gun carriage bearing Gandhi left at noon from Teen Murti House, where she had lived when her father was prime minister and where for three days her body had been viewed by hundreds of thousands of mourners.

Amid cries of "Indira Gandhi, amar rahe" (Indira Gandhi, always immortal), the cortege wound slowly through the pink sandstone government buildings erected by the British colonialists that now form the seat of the Indian government, past the imposing India Gate monument and past relatively sparse crowds on the way toward the Yamuna River cremation site. In some stretches, sizable crowds gathered, but in others mourners were not even two deep along the curbside, a sharp contrast to the overwhelming crowds that appeared following the deaths of her father and her son, Sanjay, who died in 1980 in a stunt plane accident.

A large crowd of mourners cried, "Our leader, Indira Gandhi," as the cortege emerged from under the Tilak Bridge in the broad tree-lined Bahadur Shah Zafar Road, and farther along, people showered the gun carriage with marigold and rose petals.

The crowd, pressing against the police barricades, was driven back by security forces wielding long wooden batons as the pallbearers carried Gandhi to the top of the platform and -- following Hindu tradition -- turned her head to the north before setting her down atop a stack of sandalwood.

Rajiv led the slain prime minister's relatives, including his wife, Sonia, and children, Rahul, 14, and Priyanka, 12, in placing flowers, sandalwood dust, grass, fruit and flammable liquid butter atop the body, while the pundits chanted scriptures. Priyanka appeared the most distraught of the family members at the the pyre, while Rahul, like his father, maintained his composure.

Among the mourners depositing flowers on the pyre was Maneka Gandhi, the 28-year-old widow of Gandhi's late son, Sanjay, and their 4-year-old son. Maneka Gandhi, following her husband's death, engaged in a bitter intra-family feud and formed her own opposition party to contest Rajiv Gandhi's parliamentary seat in the next general election.

Rajiv Gandhi, who has ignited funeral pyres for his grandfather, Nehru; his father, Feroze Gandhi, and his brother, Sanjay, circled the bier seven times again, following the Hindu tradition of touching a flaming torch to the flammable oil that had been applied to his mother's face.

As thin wisps of smoke curled from the base of the pyre, the new prime minister then ignited the oil-soaked logs just underneath the pallet, and other relatives quickly added sticks of sandalwood to the top of the body, completely covering it with a mound of wood.

Cabinet ministers, senior government officials, state chief ministers and other dignitaries then circled the flaming pyre, adding flammable material until it became a roaring inferno. Among them were several turbaned Sikhs, including the mostly figurehead Indian president, Zail Singh, and former chief minister of Punjab, Darbara Singh.

The almost exclusively Hindu crowd showed no reaction to the appearance of the Sikhs.

The chief minister of the southern Indian state of Andhra Pradesh, N.T. Rama Rao, whom Gandhi had sought to remove from office two months before her death in a highly controversial political move, paid homage at the pyre and was greeted by cheers from the crowd.

After briefly leaving the platform amid a crush of mourners, Rajiv Gandhi returned an hour after his initial appearance for the traditional Hindu funeral ritual of again circling the pyre seven times while holding a long wooden staff used to touch the deceased's skull -- a symbolic act that some sects of Hinduism permit instead of the traditional crushing of the skull in the belief that it releases the spirit to heaven.

When he finally left the platform at 5 p.m. and drove away, the new prime minister was cheered warmly by thousands of mourners close enough to witness his departure.

Rajiv Gandhi visited the riot- affected areas of the capital this morning and assured reporters that the government would curb lawlessness with a "heavy hand."

He said that senior law enforcement officials found wanting in the discharge of their duties would be subject to disciplinary action.

Gandhi's remarks were interpreted as attempting to counter mounting criticism by opposition parties of the inability of the security forces to end violence in the wake of the assassination. Nine opposition parties have urged the government to "effectively use the Army to curb violence and the rule of anarchy."

"The situation reminds us of what happened during the 1947 partition; innocent men, women and children are being butchered and property is being looted in an organized way as if in consequence of a sinister design," the leaders of the opposition parties announced in a press conference.

The Janata Party leadership charged in a statement that there is no leadership in the country.

General Secretary George Fernades said, "It is inconceivable that for four days it has not been possible for a government which has at its beck and call the fourth largest Army in the world to restore order ."is report.