U.S. Justice Department conciliators established a tentative truce today between two warring factions of the Chippewa tribe on this sprawling Indian reservation in north central Minnesota which erupted into violence Saturday, leaving two dead.

While quiet was restored to the reservation, heavily armed U.S. marshals from around the country arrived early today in Bemidji (pop. 12,000), about 30 miles to the south.

The marshals stockpiled crates of weapons, barbed wire and ammunition and set up communications networks.

Deputy Attorney General Benjamin R. Civiletti said in Washington today that he ordered members of the Marshals Service's highly trained Special Operations Group - equivalent to a Special Weapons and Tactics (SWAT) team - to stand by outside the reservation's boundaries in case there is an "escalation" of the situation.

He said he did so because there were only 15 tactically trained FBI agents in the area and "we might need more." Civiletti emphasized, however, that the marshals would take no action unless they were needed to enter the reservation and provide security for government property or employes.

"It's a sensitive situation," he said. "We certainly hope the truce holds."

Meanwhile, 25 FBI agents - including those with the tactical training - huddled in all-day meetings with prosecutors, poring over evidence and devising strategies in the wake of Saturday's violence which resulted in the death of boys aged 15 and 12 and destroyed millions of dollars worth of property.

The truce was reached when Indian dissident Harry Hanson negotiated a deal with officials of the Interior Department, which has authority over the Indian reservation, and the conciliators, Gus Gaynet and Patricia Glenn, both of Washington, D.C.

The agreement calls for suspension of the reservation's business superintendent, Celeste Mauss. Mauss is an ally of the tribal council president, Roger Jourdain, who has run the reservation with an iron fist for 20 years. Jourdain fled the reservation late Saturday when dissident Indians fired at least 50 rounds into his home from high-powered rifles and pistols and then burned the home down.

Jourdain's eviction was a signal victory for the dissidents, who had fought him for several months. The seeds of violence were sown a year ago when 34-year-old Stephanie Hanson, a thin, quiet former bookkeeper, sought to become the tribe's treasurer. Red Lake, like few Indian reservations, is a nation unto itself. Residents have their own police and courts and treasury and are not liable to state law, only federal criminal law.

Hanson minced no words in her campaign, accusing Jourdain and other leaders of misspending tribal funds, nepotism, violating civil rights, and keeping poor records of millions of federal dollars flowing into the reservation each year.

After her election, she also alleged that Jourdain had paid an unauthorized $170,000 in bonus payments between October 1976 and November 1978.

Jourdain temporarily suspendecd Hanson in February and removed her from the tribal council Friday night.

Early Saturday her husband, angry and armed, and eight others broke into the tribal jail, causing the political dispute to spill into violence.

"Suddenly some guys came in and got a drop on us." said David Brown, and Indian and chief guard at the jail. "They were shooting up the place, turning over desks, setting fires, destroying papers and tearing everything into shambles. Guys were drunk and they got hold of the confiscated liquor and ammunition and that just added to the problem."

By the time order was restored, after a day and night of random violence caused by an estimated 100 Chippewas, the two youths were dead and about 50 vehicles burned or shot up.

Harry Hanson said the takeover of the jail was intended to protest Jourdain's "dictorial control of the reservation" and to get the FBI to investigate Jourdain's administration.

Jourdain, since 1958 the only elected tribal chairman of the reservation, had nurtured ties to the Democratic-Farmer-Labor Party of Minnesota, winning the affections of the late vice president Hubert Humphrey and of Vice President Mondale, who aided him in his search for federal funds. He is both feared and admired in the tribe.

FBI agents have carefully avoided going on the reservation, fearing the possibility of an outbreak similar to the bloody battles between agents and Indians at Wounded Knee on the Pine Ridge Indian reservation in South Dakota in 1973.

"We are nervous. So is the U.S. Justice Department, the White House, the attorney general adn [FBI director Frank] Webster. All are vey mindful of Wounded Knee, and not injustifiable," said David Brumble, area director of the FBI.

Ealrier, another agent had said: "It's a good thing we didn't go in. They were all drunken Indians. We'd have killed them all. Maybe one of us would have gotten grazed but we'd have killed them all." CAPTION: Picture, Dissident leaders Harry and Stephanie Hanson, at left, confer with FBI men outside independent reservation. UPI