A National Guard corporal held in the murder of ABC correspondent Bill Stewart told investigators today that the killing was committed by a private who was slain in combat later Wednesday.

Thirty-two journalists, including most of the American TV network cres here, flew out of the country today. Many said they were going both as a protest against Stewart's murder and out of consideration for their personal security.

The Sandinista rebels fighting to depose President Anastasio Somoza, meanwhile, announced that the Intercontinental Hotel where scores of foreign correspondents have been living is now considered "a military target."

The hotel is across the street from the combined headquarter-residence used by Somoza within the main National Guard compound.

Cpl. Lorenzo Brenes, the National Guard corporal questioned by the military panel established by Somoza to investigate Stewart's death, said the killing was actually carried out by a Pvt. Gonzales who was killed a few hours later in combat against the Sandinistas.

Brenes told the investigating officers that Gonzales told him he shot Stewart "because he tried to run away."

Film taken by Stewart's ABC colleagues showed him lying on the ground when he was shot.

Pablo Tiffer Lopez, driver of the ABC van who witnessed the killing, told the panel that a solider at the scene came up to him and said, "I'm sure he's no journalist. He's a dog."

Stewart's body was flown out of the country by a U.S. Air Force plane. Also aboard were the crews from the American networks. The New York home offices of the three networks said they had left it up to the individual to decide whether to leave.

Meanwhile, both the Sandinista National Liberation Front and the National Guard announced that a Sandinista airplane bombed targets in Managua at 1 a.m. today.

The attack was the first substantive indication that he guerrillas have the use of aircraft.

Sandinista radio claimed a hit last night on the "bunker," as Somoza's headquarters is called. The government claimed the Sandinistas bombed a hospital, various houses and a refugee center.

There was no way to confirm either report, although informed sources said two homes had been hit by nine small bombs in the western part of the city, injuring one woman. While many persons in Managua claimed to have heard the plane fly over, there was no indication as to what type of aircraft it was or what form of ordnance it dropped.

Previously, the Sandinistas never commented on government reports that they were using planes, presumably based in Costa Rica, to ferry supplies and reinforcements.

There was little fighting today in Managua. Source reported heavy government rocket attacks on Diriamba, a small city 30 miles south of here that is partially occupied by guerrillas.

The government waited nervously for news form an emergency meeting of the Organization of American States in Washington, where foreign ministers of the 27-nation body were discussing the Nicaraguan situation.

There was no immediate official response to a call by U.S. Secretary of State Cyrus Vance for a transitional government, assumedly without Somoza, and the formation of an OAS peace-keeping force to be sent here to impose a cease fire.

Julio Molina, a prominent opposition member in Nicaragua's Congress said here that the only solution to the crisis was Somoza's resignation. Molina said that he and other political leaders had proposed to the OAS, through the United States, a constitutional replacement government" headed by an opposition member of Congress that could be acceptable to the Sandinistas. He said that he felt a cease-fire, imposed by an OAS peace-keeping force, would not be respected by either side.

"Both now think they can win," Molina said.

Before their evacuation today, two ABC technicians who witnessed and filmed Stewart's execution signed statements recounting the incident and gave the government a copy of the footage.

Soundman Jim Cefalo and cameraman Jack Clark said Stewart had approached a national guard patrol in a quiet Managua neighborhood on foot with his interpreter, while they and a driver waited behind in a van.

They said a soldier ordered Stewart, who had his hand raised, to this knees and then to lie flat on the ground. The soldier than kicked Stewart and shot him once in the head. The interpreter, Juan Francisco Espinoza, was also shot dead.

Brenes had no been formally charged with the murder and today was questioned in a preliminary hearing. While he first told reporters that the soldier who shot Stewart was named Pedro Gonzales, he later told three military judges he could not remember the soldier's name.

Still dressed in camouflage fatigues and with mud on his boots, Brenes, a 27-year-old platoon leader from the northern city of Matagalpa, appeared to understand little of today's proceedings. Early in the morning, while he sat without guards in an anteroom, he answered reporters' questions in terse sentences while staring at the floor.

Before the judges, when asked if he swore to tell the truth, Brenes said "No."

His appointed attorney, National Guard Maj. Arturo Vallejo, said later that Brenes was uneducated and "probably didn't understand the question." Vallejo said that executions such as Stewart's were common "on both sides" of the Nicaraguan war. He said that no Nicaraguan soldier had ever been brought to trial for such executions before.

In further testimony, Brenes said he was on patrol and "saw some soldiers half a block away from where the gringo (Stewart) died.I saw the soldiers talking to the man, unfortunately when I started walking toward them . . . I heard a shot. I arrived and asked the soldiers what happened. The journalist was already dead . . . I continued on my mission."

Asked if he knew why Espinoza, the interpreter, had been shot, Brenes said he was "a suspect. He worked as an [airport] porter. Three of the soldiers said they knew him . . . that he had left his job months ago and wasn't a porter any more. They killed him as a suspect."

Neither of the two Americans who witnessed the incident but left today, nor their Nicaraguan chauffeur, was asked to identify Brenes. CAPTION: Picture 1, Cpl. Lorenzo Brenes of Nicaragua's National Guard tells foreign reporters that he did not kill Bill Stewart. AP; Picture 2, Nicaraguan troops advancing in Managua come upon a former rebel barricade. UPI; Picture 3, Nicaraguan rebels man recoilless rifle in action near La Virgen Wednesday. By Nicaraguan solider Emilio Via Associated Press; Picture 4, Sandinistas guerrillas lead away a government soldier captured in Sapoa. By Nicaraguan soldier Emilio via The Associated Press