A Honduran Army helicopter flew the bodies of two slain American journalists to Tegucigalpa for shipment home today as the Nicaraguan government rejected charges that fire from its soldiers killed the reporters as they drove along the Honduran side of the embattled border yesterday.

Dial Torgerson, 55, of the Los Angeles Times and Richard Cross, 33, a free-lance photographer on assignment for U.S. News and World Report, were the first American journalists killed in the expanding war in southern Honduras. Obituaries on Page B6.

Their white, four-door Toyota sedan was destroyed yesterday afternoon by a rocket-propelled grenade that Honduran and U.S. authorities said was fired by Sandinista soldiers from within nearby Nicaraguan territory.

A third man, originally said to have been the driver of the journalists' car, was identified today as a Honduran civilian who was walking near the car when it exploded. According to a Honduran military spokesman, the man, Jose Herrera Rodriguez, 27, was severely wounded by the force of the explosion and was operated on in Tegucigalpa this afternoon.

The Nicaraguan Foreign Ministry, in a statement issued in Managua, denied the Honduran charge. It said no Sandinista soldiers fired into Honduran territory, and depicted the journalists as "victims of the criminal violence that the United States government has unleashed in Central America, particularly along the Nicaraguan-Honduran border."

In Washington, Secretary of State George P. Shultz said "the fire" that killed the two newsmen "did come from Nicaragua." A State Department spokesman said, "We will, through our embassy in Managua, protest this deliberate attack on civilians in Honduran territory."

Torgerson and Cross had gone to the border area to investigate the escalating charges and countercharges about fighting there. Their deaths now appear to have become part of the controversy, with Nicaragua seeking to to incriminate Honduras and the United States and Honduras seeking to do the same to Nicaragua.

For the past nine months, the Sandinista government has been complaining about U.S. and Honduran support for Nicaraguan insurgents operating from bases here and mounting increasingly bloody attacks in northern Nicaragua. Simultaneously, Honduras has been charging Managua with frequent cross-border shellings and raids, which U.S. and Honduran officials say have increased sharply during escalated fighting just inside Nicaragua in the last two weeks.

"From this moment, the Honduran government holds the Nicaraguan government responsible for whatever incidents could occur as a result of the constant harassment by the regular Nicaraguan Army against Honduras' territory and population," Honduran Foreign Minister Edgardo Paz Barnica warned in a protest handed last night to the Nicaraguan charge d'affaires, Carlos Sequeira.

The Honduran Army said its men trucked the two bodies to the border settlement of Las Trojes last night from a roadside spot, where they had lain several hours while gunfire prevented access.

Cross' body was flown to Miami on a commercial airliner this afternoon for shipment to Los Angeles, where his father lives, according to U.S. Consul Sarah Horsey. Torgerson's badly damaged body, carried in a plastic sack, was held in a Tegucigalpa morgue until his widow, Linda, arrived aboard a chartered jet from Mexico City and returned to Los Angeles with the body.

Jose Cruz Espinal, who was driving a truckload of wood along the border road from Las Trojes to Cifuentes, said the rocket-propelled grenade slammed directly into the car window, lifting the car into the air and setting it afire in a loud explosion. Such grenades, fired from shoulder-held rocket tubes, are designed to cripple armored vehicles. The explosion "completely destroyed" the light, unmarked car, Cruz said at a news conference arranged by the Honduran Army.

With Army spokesman Cesar Elvir Sierra at his side, Cruz said the grenade was fired from inside Nicaragua at the spot known as Quebrada de la Vigia, about 2 1/2 miles west of Las Trojes and, he said, only about 30 yards north of a low wire fence marking the border. According to U.S. military sources, the Soviet-designed RPG-B7, a rocket-propelled grenade launcher in common use by the Nicaraguan Army, has an effective range of between 350 and 550 yards.

Cruz, a Honduran civilian, said Nicaraguan soldiers sprayed the area with automatic weapons fire after the car was hit. Although he said he did not see who fired the gun or grenade launcher, he asserted that the assailant must have been Nicaraguan since the fire came from within Nicaraguan territory.

The long-tense border area has been the scene of intensified fighting in the past two weeks as U.S.-backed Nicaraguan guerrillas have stepped up their attacks in Nicaragua's Nueva Segovia Province just south of that section of the border.

The rebels captured the Nicaraguan village of El Porvenir near the border two weeks ago in some of the conflict's most severe fighting so far. After holding it for several days, they lost control to a Sandinista counteroffensive a week ago.

A source in the high command of the Nicaraguan Democratic Force, the main counterrevolutionary group, said the El Porvenir battles have been particularly violent because the area's insurgent commander, known as "Suicida," was seeking vengeance for the death of his wife, who was killed three weeks ago on the same road where Torgerson and Cross were slain.