With a cartridge belt around his waist and a high-powered hunting rifle on the porch of the farmhouse, Alain Lapelerie described his suspicions when native Kanak tribesmen began gathering two weeks ago at a house about 500 yards up the road.

For days, said the 28-year-old son of French settlers here, he and his brother, Michel, 30, lived in fear of an attack by armed militants of the Kanak Socialist National Liberation Front, which is seeking independence for the indigenous Kanaks, or Melanesians, of this French overseas territory.

The Lapeleries said they were convinced that the Kanaks' aim was to drive the last remaining white European settlers out of this hilly area of central New Caledonia and attack the town of La Foa, about 10 miles to the south.

Whether the Kanak militants actually harbored any such plan may never be known for certain, since, after a neighbor was beaten up, the Lapeleries called in the French gendarmerie.

The police surrounded the Kanak house and, following a siege in which police calls to surrender and the firing of tear-gas canisters and stun grenades reportedly were met with rifle shots, elite French sharpshooters killed two Kanak leaders. One of them was Eloi Machoro, the minister of security in a Kanak "provisional government" and perhaps the most hard-line Kanak.

After the shooting by the National Gendarmerie Intervention Group, 37 Kanak militants in the house surrendered and were arrested. Afterward, police confiscated 35 rifles, many of them reportedly stolen from European settlers in the eastern coastal town of Thio, as well as explosives and ammunition.

One of those arrested was a young Kanak named Bernard who had worked on the Lapelerie farm until about October 1984, when militant Kanaks began agitating for a boycott of the Nov. 18 territorial elections to press demands for independence.

For a time, Bernard had even been in a partnership with Michel Lapelerie in farming a separate tract of land a few miles up the valley, and he had often visited this modest tin-walled farmhouse here to have lunch with Michel and his Indian-Japanese wife, Brenda, the family said. They described Bernard as a moderate supporter of independence.

Then, they said, he was either "threatened" or "brainwashed" by Kanak militants and abruptly quit working for the Lapeleries. Nevertheless, they said, they were surprised when they learned he was among those arrested after the Jan. 12 siege.

Now, it looks as if it is the Lapeleries who are under siege.

Since that Saturday morning, Alain Lapelerie said, tensions have abated somewhat, but the family remains vigilant against attempts to take over the 3,000-acre farm. Determined to stay, the Lapeleries have armed themselves with several rifles, set up sandbagged positions with alarm systems and spotlights to defend the approaches to the property, and organized watches.

While many settlers have fled -- the Lapeleries are the last ones in their area -- other determined Europeans have turned their farms into similar armed camps elsewhere on this South Pacific island. According to a newspaper in Noumea, the capital, some also have started to organize defensive networks to come to each other's aid in case of attack.

While the European settlers and immigrants from Asia and the Pacific make up 57 percent of the population and predominate in the capital, the Kanaks form the majority in the countryside.

The fortifying of European enclaves in la brousse -- the bush or countryside -- reflects not only a lack of confidence in French authorities to assure protection but a growing political and racial polarization between settlers and Kanaks.

The racial aspect of the independence problem is one that many New Caledonians are loath to acknowledge in a racially mixed society that has long prided itself on its harmony. But three months of violent agitation by independence-seeking Kanak militants evidently has driven many of the black tribesmen apart from the broussards, or white settlers, in their midst, with each side accusing the other of racism.

"We've reached a stage where we don't trust any black fellow, which is a shame because there are a lot of good ones around," said Alain Lapelerie. "A lot of people refuse to believe the blacks would hurt them because they had such good relations, but they were bitterly disappointed."

He complained that outsiders "all seem to ignore the fact that the Kanak Socialist National Liberation Front wants black independence. They want us out of here."

For the Kanak militants, families like the Lapeleries, even those who have been in New Caledonia for generations, are "colonists," and sovereignty over the islands rightfully belongs to the indigenous people. Kanak Front leaders have said that the "Europeans" born here and other settlers can stay on in an eventual Kanak-run independent country, but under what circumstances and with what guarantees remain subjects for negotiation.

Many broussards and other settlers clearly have little faith in the guarantees proposed by the French special envoy, Edgard Pisani, in a plan announced earlier this month to give the territory independence "in association" with France.

"How can Pisani give guarantees when he's not even going to be in power?" asked Alain Lapelerie. "Whatever guarantees the French give will be wiped out" under a Kanak-ruled independent state, he asserted.

Nevertheless, the French authorities appear to be trying to reassure settlers like the Lapeleries by posting gendarmes in the area. An observation post manned by several members of an antiterrorist squad has been set up on a hill overlooking the Lapeleries' valley farm, and a unit of the paramilitary Gardes Mobiles checks traffic at a roadblock about half a mile away.

However, according to Lapelerie's father, Andre, who owns the farm, the gendarmes have informed him that they cannot permanently assure security because of the remote location of the property. Therefore, he warned in a tough letter to Pisani last week, he would take the necessary measures himself, would treat any intruder as an "enemy" and would hold Pisani responsible for the consequences.