Ten members of a native pro-independence group were shot to death last night, setting back efforts by the French government to reach an agreement with separatists and settlers on the future status of this South Pacific island territory.

The 10 were killed when gunmen presumed to be French settlers opposed to independence opened fire on them in the village of Hienghene on the northeastern coast of New Caledonia. The dead included two brothers of Jean- Marie Tjibaou, the leader of the Kanak Socialist National Liberation Front and head of a "provisional government" of an anticipated independent state.

Another brother was among four Kanaks wounded. Three other militant natives were reported missing.

A new French high commissioner of New Caledonia, Edgard Pisani, who arrived here Tuesday to seek a solution to the independence dispute, ordered an investigation into the killings and pledged that the perpetrators would be arrested. He said that despite the "tragic event," progress was made today toward restoring order when French authorities released 17 militant Kanak prisoners in return for the removal of several Kanak roadblocks and the evacuation of some public buildings that had been occupied by militants, including at least three police stations.

Tjibaou said that the Kanak Front would keep its part of the bargain by removing the rest of its roadblocks and vacating other occupied buildings, and he called on his followers to remain calm.

However, an address by another Kanak Front leader to about 50 militants gathered at Tjibaou's headquarters here left no doubt that the negotiations could be in jeopardy.

"We are facing people who want to massacre us," said Iewene Iewene, a minister in the Kanak provisional government and spokesman for the front's politburo. "We are facing barbarians with guns. We must absolutely develop a new strategy."

Iewene added, "We must now organize a counterattack," but he did not elaborate. In the meantime, he called on the militants to "first organize your own security" and "remain vigilant."

Iewene said that after a mourning period for their 10 dead comrades, the Kanak Front would hold a meeting to discuss a new strategy and decide whether to negotiate with the French government on the future of the territory.

Pisani had announced yesterday his intention to hold talks with all political groups in New Caledonia starting Dec. 15 provided order has been restored. He said he would submit a proposed solution to the French government by Feb. 2.

Members of one of the more radical groups in the Kanak Front told reporters at a roadblock about 60 miles northeast of Noumea that they were not party to an agreement to remove their barricades and indicated that they were not under Tjibaou's control. Several of them were armed with shotguns, hunting rifles and machetes.

There was no indication today that French police and Army troops had intervened yet to stop violence between Kanak tribesmen and settlers, which started when militant Kanaks launched a campaign last month to boycott local elections Nov. 18 and agitate for independence. The worst incident last night occurred at about the time that Pisani was appealing to New Caledonians in a live radio and television address to help restore order in the remote French island territory. French authorities were not immediately able to reconcile conflicting versions of the killings.

According to the Kanak Front, 17 members riding in two vehicles were ambushed at a French loyalist group's roadblock after leaving a meeting in Hienghene, of which Tjibaou is the mayor. Afterward, this version says, other Kanaks retaliated by burning a settler's house.

According to local French loyalist authorities, however, the Kanaks burned the house and then came under fire while trying to attack a second settler's house. The Kanaks' two vehicles were then burned.

French authorities said that the owners of the burned house were being questioned and that others suspected of involvement in the incident were being sought by about 100 police stationed in the town. A number of French settlers in the area sought police protection today, and 51 residents were evacuated from Hienghene by French military aircraft.