Most of the Nicaraguan troops who entered this Honduran border area five days ago to battle anti-Sandinista rebels based here have withdrawn from the country, U.S. and Honduran officials said today.

The Honduran government, seeking to bring the recent fighting under control, has ordered the Nicaraguan rebels to stay in their camps and not pursue the retreating Sandinista forces, according to sources in the Honduran capital of Tegucigalpa with access to intelligence reports. They spoke on the condition that they not be identified by name or nationality.

The Nicaraguan troops pulled back after failing to take a rebel training center about 10 miles inside Honduras that was their principal objective, according to U.S. accounts.

In Managua, the Nicaraguan Defense Ministry said its troops had "destroyed important enemy camps" along the border, although it did not say the camps were inside Honduras. Earlier, Nicaragua had denied reports of the attack on the rebel bases.

[In Washington, there were conflicting reports about whether a helicopter carrying CIA employes had crashed or been forced down near the Honduras-Nicaragua border.]

"The majority [of the Nicaraguan soldiers] are outside" Honduras now, Honduran Lt. Col. Danilo Carbajal told 60 reporters who were flown here this afternoon for a visit. Another Honduran officer estimated that only 100 Nicaraguan soldiers were still inside the country.

Honduran and Nicaraguan residents in this small village eight miles from the border said there was heavy fighting in Honduran territory east of here on Sunday and Monday, as the U.S. government has said. The residents, who said they had heard weapons being fired and talked to persons fleeing the fighting, also said that the cause of the combat was a Nicaraguan incursion.

The Honduran Army displayed five bodies clad in tattered camouflage fatigues and said they were Sandinista soldiers killed Tuesday. The Army also displayed 36 AK47 automatic rifles, four machine guns, two rocket-propelled grenade launchers, a missile launcher, ammunition and other military gear that it said had been captured from the Nicaraguans in Honduran territory.

The equipment on display included several large white pieces of cloth stamped "Sandinista Popular Army," and one of the machine guns had markings in Cyrillic letters that indicated that it had been manufactured in the Soviet Union.

U.S. Army helicopters completed an airlift of 600 Honduran troops to the border region today. The airlift, which began yesterday, was aimed primarily at establishing a symbolic presence along the border to assert Honduran sovereignty, according to Honduran and foreign sources.

The Nicaraguan withdrawal and the Hondurans' move to rein in the rebels, who are known as contras or counterrevolutionaries, appeared to mean that the controversial Nicaraguan incursion was winding down.

U.S. officials now say their initial estimates that 1,500 Nicaraguan troops had participated in the incursion may have been exaggerated. Honduran and other sources here, who declined to be identified, estimated that at most 800 Nicaraguan soldiers were involved. These sources said the U.S. administration pumped up its estimates to discredit the Sandinistas and thus help persuade Congress to approve U.S. aid to the contras.

Honduran Col. Carbajal said, however, that the Honduran armed forces had monitored radio messages among Sandinista units indicating that 1,200 Sandinista soldiers had participated. The colonel's comments today marked the first time that a Honduran government representative has officially estimated how many Nicraguan troops were involved.

The Nicaraguan Defense Ministry statement said 40 Sandinista soldiers and 350 rebels were killed in fighting along the Nicaraguan-Honduras border in the last week. It said 250 contras and 116 Nicaraguan soldiers were wounded. The statement added that five Sandinista soldiers were missing, including two who are in Honduran custody, an apparent reference to two men presented to journalists in Tegucigalpa Wednesday.

It said Sandinista troops "destroyed important enemy camps, including the enemy's principal training center."

In Washington, several government sources reported the downing of a helicopter with CIA employes aboard, although it was unclear whether the helicopter had been fired upon or had malfunctioned.

[An administration official, asked to comment on the reports, said, "There has been no U.S. civilian or military helicopter fired on, crashed or anything else."]

The U.S. government granted $20 million in emergency military aid to Honduras on the strength of the incursion, which was announced in Washington. Honduran officials have insisted that they did not initiate the request for the aid, and reliable sources said the U.S. government told the Hondurans that extra aid would be available if they asked for it.

Senior Honduran officers insisted that the Honduran Army had killed the five soldiers that were shown to reporters, and that the Hondurans also had captured the equipment that was on display. This was denied, however, by a Honduran sergeant, who was interviewed separately, and by several other well-placed sources who declined to be identified.

The sergeant and the other sources said the contras had killed the Sandinistas and captured the equipment and given them to the Hondurans to show the media.

Peasants here said there was heavy fighting, including artillery bombardments and rocket attacks, beginning Saturday east of here. The main Nicaraguan thrust into Honduras took place about nine miles to the east, according to Honduran and U.S. officials.

United Press International reported the following from Managua:

Cardinal Miguel Obando y Bravo, charged in a Holy Thursday service that the official Sandinista media are "crushing" the nation's Roman Catholic bishops.

"The devil can be reincarnated in certain people who wish to divide the church," Obando y Bravo told about 5,000 persons celebrating mass, and Nicaragua's bishops "are being crushed by the official media."