Despite massacres and spreading anarchy in Liberia, the United States has decided not to intervene in the conflict on grounds that the warring factions have spurned previous calls for peace and that none of the protagonists is worth supporting, administration officials said yesterday.

"The bottom line is, it's not in the United States's interest to get in the middle of this fight. It would be like going into Beirut. It is not something we would put U.S. boys on the line for," said a senior State Department official.

Yesterday, soldiers of President Samuel Doe beat or shot to death hundreds of civilian refugees, according to eyewitness reports from the Liberian capital, Monrovia.

The besieged Doe is battling two rebel groups who launched an offensive seven months ago, accusing him of corruption and human right abuses. Doe has vowed to make a final stand inside his fortified mansion, and one of the rebel groups, headed by Prince Johnson, has advanced to within a mile of Doe's headquarters in Monrovia, while the other group, the National Patriotic Front headed by Charles Taylor, was fighting government troops six miles outside the capital.

The White House and the State Department condemned the massacre yesterday as a "senseless act of terror." Five European ambassadors in Liberia over the weekend called for U.S. military intervention and for an urgent U.N. Security Council meeting.

But U.S. officials said American intervention remained out of the question, except for a standing offer to evacuate Doe if that would avoid bloodshed. "The administration believes that it's not our role to intervene, to engage in peacekeeping or to impose a government or political system in Liberia," State Department deputy spokesman Richard Boucher said yesterday.

During the 1980s, Liberia received heavy infusions of U.S. aid, and American interests there include an Omega communications and navigation relay station, a Voice of America transmitter, and a tradition of short-notice landing rights for U.S. military aircraft. Boucher said there have been no direct threats against the 400 Americans remaining in Liberia.

Explaining the U.S. reluctance to get involved, the senior State Department official, who spoke on condition he not be identified by name, said, "The U.S. has not found any of the parties in this conflict to be people we can stand up and support. They have all said various things about democracy but none of them have any proven democratic credentials." The official said that a United Nations peacekeeping attempt would probably fail, just as U.S. calls for negotiation are being ignored.

In a statement later yesterday, the State Department urged "all concerned states" to press for a cease-fire and said that if "they also see a constructive role for the United Nations to play in this situation, we would be willing to look at it most seriously."

Claude Ake, a Nigerian political economist who is a guest scholar at the Brookings Institution, said that while the United States does not have "overwhelming material interests" in Liberia's plight, it does have a larger interest based on "a special historical tie" with the nation. "It has been one of the most reliable allies," he added. "There was an opportunity to make Liberia a sort of showcase of American involvement in the Third World. That opportunity was unfortunately not realized. From that point of view, America does have some interests in setting things right."

"The state of anarchy has put many more people in more jeopardy. There is a need for somebody to intervene," he said. Even if Doe flees or is removed, he said, there is likely to be a protracted fight for power.

Even if the rebel groups "are not likely to listen" to appeals from the United Nations, he said, "I don't think that's any reason for the Security Council not meeting. They should meet anyway and explore the feasibility for some peacekeeping role."