Amid a campaign by fundamentalist Sikhs to raise a "sacrifice" force of 100,000 volunteers to confront India's central government, concern is rising that extremism is sweeping the movement for an enlarged and virtually autonomous Punjab state.

Leaders of both the moderate and radical factions of the chauvinistic Akali Party here support the force of "martyrs" and say that its aims will be peaceful unless it is provoked. But moderate Sikhs and Hindus fear the possible eruption of communal clashes reminiscent of the recent violence in the far northeastern state of Assam, where at least 3,000 persons were killed.

An escalation of Sikh riots, bombings, murders and clashes with police, coupled with recent arms raids on state armories in the Punjab and neighboring Rajasthan, has heightened alarm and drawn attention to two sants, or holy men, who control the two largest factions of the fundamentalist Sikh movement.

Sant Harchand Singh Longowal, president of the Akali Party and leader of a two-year-old Sikh agitation for Punjab autonomy, said in a wide-ranging interview here that he is in control of the movement at the moment and commands the loyalty of young, militant followers of the 37-year-old radical preacher, Sant Jarnail Singh Bhindranwale.

But shortly after 30,000 Akali volunteers, including Bhindranwale, took an oath to make the "supreme sacrifice" for the Sikh cause, Longowal conceded, "Those young men who take it upon themselves, by way of the heat of their blood, to adopt violent methods, I cannot rule it out. If anyone takes to violence, it will be the responsibility of the government."

For his part, Bhindranwale said in an interview in his spartan quarters adjoining the Sikhs' sacred Golden Temple here, "It is up to the government if they want to be peaceful or violent. We are determined to achieve our goals. The Sikh is fearless, and if he has any fear in his mind, he is not a Sikh."

He added, "This movement cannot get out of my control. I wish to be peaceful, but if the government doesn't want us to be peaceful, maybe some hot-blooded types might get out of control."

These contrasting perceptions as to who has the allegiance of the young radicals of the Akali movement underscored the potential for a major flareup of violence in the holy city and elsewhere in the Punjab, where in the last year more than 100 persons have been killed and an estimated 50,000 have been arrested and jailed in confrontations with federal and state security forces.

The unpredictability of the volatile Sikhs, whose history of militarism dates back to their ferocious battles with the Mogul invaders, was graphically illustrated during the weeks following clashes across the Punjab on April 4 that left 20 persons dead and hundreds injured.

Bracing for widespread confrontations last Wednesday on the 64th anniversary of the Jallianwalla Bagh massacre, in which British troops opened fire on a peaceful Indian protest and killed or wounded 1,516 persons, security forces were startled when the expected Sikh demonstrations failed to materialize.

Similarly, the swearing-in of the vanguard of the Akali "martyrs' squad" the following day, which coincided with the anniversary of the holy admonition to the Sikh militaristic brotherhood by Guru Gobind Singh in the 17th century, inspired no demonstrations outside the Golden Temple, possibly because of torrential downpours that flooded the streets of this northern Indian city.

But Indian security forces and wary Punjabi Hindus, who comprise slightly under half of the 16 million population of the state, say that the calm is deceptive and that renewed violence is always possible.

A Central Reserve Police Force officer leading one 30-man patrol in the bazaar near the Golden Temple said he had ordered his men to keep their rifles loaded and to be prepared to fire if necessary with the onset of any violence. A veteran of security duty in the insurgent-prone far northeastern states, he described Amritsar as "tense as long as there are mischief-makers here."

A Hindu druggist recounted incidents of radical Sikhs chasing terrified Hindus through the bazaar and stabbing them with swords, although he said most Hindu and Sikh merchants are on friendly terms and live in mutual fear of the zealots.

The druggist said many shopkeepers were sustaining business losses because they have shuttered their stores during periodic disturbances, adding, "We are preparing for the worst."

Bhindranwale, an obscure village preacher before he almost overnight became a hero to young radical Sikhs, sat on his camp bed in the four-story whitewashed Guru Nanak guest house adjacent to the architecturally spectacular Golden Temple and told a visitor that the confrontation has put at stake nothing less than the survival of Sikhism, a religion founded in the 15th century as a fusion of Hinduism and Islam.

Talking almost nonstop through an interpreter for more than an hour, surrounded by turbaned guards carrying long curved swords and spears, Bhindranwale evoked images reminiscent of Ayatollah Ruhollah Khomeini during the early days of the Iranian revolution as he recounted a litany of alleged atrocities against Sikh martyrs.

Indeed, the nearby Golden Temple museum is replete with death-pose photographs of Sikhs killed in recent clashes, their images daubed with red paint in a fashion common to displays of martyred Iranian revolutionaries.

"Peace and violence are from the same root. We are like a matchstick that is made of wood and is cold. But when you strike it, it flames," said Bhindranwale, who has taken sanctuary in the protected Golden Temple compound as a fugitive after being implicated in the murder of a Hindu newspaper editor here and accused of a variety of security offenses.

Bhindranwale spoke bitterly of Prime Minister Indira Gandhi, calling her "that Brahmin girl who is prime minister and is given more status than the Sikh scriptures." He complained that Sikhs arrested for hijacking airliners languish in prison, while two Hindu supporters of Gandhi's Congress (I) Party who in 1978 hijacked an Indian airlines plane in an attempt to force the release of Gandhi from jail were released on the prime minister's orders after she returned to power and were given seats in state legislatures.

Of the "sacrifice force," Bhindranwale said, "those volunteers who took the oath will be used if worse comes to worst. If the government is not prepared to budge, then we will use that force."

Although Gandhi has made concessions on several of the Sikhs' religious demands--that Sikh hymns be broadcast over All-India Radio from the Golden Temple; that the sale of alochol, tobacco and meat be banned near the temple; and that Sikhs be permitted to carry nine-inch kirpans, the daggers they wear as a religious practice, aboard airliners--most of the political demands remained unresolved.

Both Longowal and Bhindranwale agreed that fulfillment of the outstanding demands must include:

* Enlarging the Punjab's boundaries to include Punjabi-speaking areas of surrounding states and giving it autonomous powers that no other Indian state has except the strategically important and contested Moslem state of Kashmir.

* Redistributing the river waters of northern India to the benefit of the Punjab.

* Moving the capital of the Punjab from Chandigarh to Amritsar, and declaring the latter a holy city.

* Release of Sikhs arrested in confrontations with the central authority.

Leaders of the fundamentalist Akali Party, which was formed in 1920 to remove the Hindu influence from Sikhism, continue to insist that their movement is basically a religious one, intended to ensure the survival of Sikhism.

Bahn Singh, secretary of the committee that oversees Sikh temples, said, "They the government officials want to drown the Sikhs in the Hindu sea. They want to assimilate the Sikhs into their majority. They are squeezing the blood of the Punjab and giving it to other states."

But the movement is increasingly taking on the appearance of an attempt to gain political power in an Indian union whose central control has been steadily rising under Gandhi's leadership but that has been increasingly strained by the centrifugal forces of regionalism.

Following the unprecedented violence in Assam and electoral losses for Gandhi's Congress (I) Party in southern Indian states, the prime minister has been viewed by some militant Sikhs as being vulnerable to political pressure for concessions on demands for autonomy.

By the same token, however, the specter of another communal bloodbath like Assam--this time closer to the capital and in the middle of the northern Indian Hindu belt--could cause Gandhi to draw the line on concessions and ride out whatever storm ensues.

In the meantime, officials in New Delhi are closely watching events in Amritsar to determine whether Bhindranwale's radical forces truly are on the ascendancy and whether they can push Longowal into a more extremist stance.

For the present, Longowal, while insisting he still is in charge of the Akali movement, appears to be treading lightly in both camps.

With Bhindranwale-like rhetoric, he recently told reporters that Gandhi "should stop playing with fire. This is not Assam. We will die like soldiers at the hands of the police."

But in an interview, he said that he had ordered a temporary halt to demonstrations and that he hoped for progress on negotiations with the central government.

The imponderable remains whether in the face of continued sluggishness of the negotiations, the Akali leadership can restrain the 100,000 self-professed "martyrs" it plans to enlist by May 12 and keep the lid on the rising political and religious passions in the Punjab.