PALALI, SRI LANKA, JULY 31 -- Tamil guerrillas today gave no indication that they were prepared to lay down their arms in exchange for substantial autonomy in their home areas as prescribed in the peace accord signed by the leaders of Sri Lanka and India on Wednesday.

More than 3,000 Indian troops have arrived in Sri Lanka to help enforce the agreement, but there was no sign that they had persuaded the Tamil insurgents, who, like most Indians are Hindus, to cooperate in bringing a halt to the ethnic violence that has cost an estimated 6,000 lives in the past four years.

The agreement calls for a cease-fire, beginning today, followed by disarming of the guerrillas.

"Apparently there is a communications gap, a problem in getting the word out," said Lt. Gen. Depinder Singh, head of the Indian Army Southern Command, who was visiting his troops today at the main air base and Army post on the contested Jaffna Peninsula.

While the accord was running into trouble here in northern Sri Lanka, the government remained besieged by protests in the southern part of the country by the predominantly Buddhist Sinhalese majority, which believes Sri Lankan President Junius Jayewardene has sold out their interests.

A member of Parliament from the ruling party was reported killed today by a mob near Galle in southern Sri Lanka and two demonstrators were reported killed by police in the central part of the country as they tried to set fire to a Cabinet member's house.

Under the accord signed by Jayewardene and Indian Prime Minister Rajiv Gandhi, a 48-hour cease-fire was to be followed by a 72-hour period during which Tamil guerrillas, who have been battling the Sri Lankan government since 1983, would surrender their arms.

If the Tamils stop fighting, the agreement calls for the Sri Lankan government to grant, among other things, a significant degree of autonomy in the Tamil-dominated Northern and Eastern provinces of Sri Lanka.

Officers of the Indian peace-keeping force that began arriving here yesterday morning admitted that the process could take longer.

There also were suggestions that Indian troops may seize arms from the Tamil guerrillas by force, opening the possibility of violence between predominantly Hindu Indian Army units and Hindus in the Tamil guerrilla forces.

Sri Lanka's Tamils have been fighting for increased rights and regional sovereignty. The accord signed Wednesday calls for the Tamils to end the armed conflict, and in return the government, among other things, will give a significant degree of autonomy in the Northern and Eastern provinces.

In Jaffna, Sri Lankan Army units continued to board Indian Air Force planes today to be ferried south for riot-control duty. The Indians were using both twin-engine propeller planes and giant four-engine Soviet-made Ilyushin 76 jet cargo planes to bring in more Indian troops and equipment and to ferry out the Sri Lankans.

The sophisticated equipment clearly impressed Sri Lankan military officers.

The Indians also made their presence felt in Colombo, the capital, where two frigates were anchored.

The Indian forces appeared to be having trouble gaining the confidence of the main Tamil guerrilla group, the Liberation Tigers of Tamil Eelam.

With their leader, V. Prabhakaran, staying in a New Delhi hotel under heavy guard, local guerrilla forces seemed unwilling to give up their weapons.

Gen. Depinder Singh said, "They have been awaiting word from Prabhakaran. So far, they have not got it."

A Sri Lankan journalist reported that Maj. Gen. Harkirat Singh, commander of the Indian forces on the Jaffna Penninsula, met with other guerrilla leaders at the village of Tellippalai but left quickly when the crowd suddenly turned hostile.

Singh said he had "some impact" with an emotional appeal to the guerrillas to cooperate.

"They want to go home," he said. "They are keen to come back to their homes. There were tears in the eyes of the women."

But he also admitted that the crowd became hostile and began to shout for the return of their leader, Prabhakaran.

Indian officers admitted today that the task of disarming the guerrillas may now take "five or seven days" instead of the 72 hours called for in the accord. They said they plan a propaganda leaflet campaign to explain the accord to people on the peninsula. Ultimately, however, according to Depinder Singh, the Indian forces are prepared to take arms by force.

"Our first task, after separating the forces here, is to fan out into the interior and establish contact with the militants and give them confidence they can come out," Singh said. "That is the goal, to establish contact. The process has started, but it will take time."

A second meeting with Tamil guerrilla leaders was under way late this afternoon, but there was no report of its outcome.

Sri Lankan troops leaving the Jaffna area were clearly pleased to turn their task over to the Indians.

"The war is over," said D.N.S. Bandara, 22, a lieutenant with two years' service in the Jaffna area. "We are going home. It is all because Rajiv Gandhi came."

Officers of higher rank expressed some unease, despite Sri Lankan Army commander Cyril Ranatunga's statement today that his forces are "very happy" to have Indian troops here.

One officer said, "We haven't seen the accord. Our guys are very angry the Indians are here. They don't realize how difficult things are for us. We don't know how long they will stay. They say a few days, but we don't know."

Elsewhere in the Jaffna area, however, there were signs the accord was having the desired effect.

In Palali, near northeastern Point Pedro, a busload of residents showed up this afternoon on their way home from Jaffna, where they had gone for refuge a month ago when fighting was heavy near their homes.

"We heard over the radio that everything is okay, so we are coming home," said N. Kumar, the bus conductor. "The agreement is a good thing. We like peace. That is what we want."

A passenger, V. Yogathasam, coming home with his four children, said, "If they stop fighting, both sides, it would be good now."