ATLANTA, NOV. 25 -- The Defense Department sent a team of military "advisers" today to the Atlanta Federal Penitentiary, where nearly 1,400 Cuban inmates rioting for a third day held 94 hostages. But U.S. Bureau of Prisons Director J. Michael Quinlan said the penitentiary would not be stormed as long as the hostages were safe.

"We will take no invasive action . . . unless some steps are taken to harm the hostages," Quinlan said at a Washington news conference. "My patience is endless." About a dozen federal agents, however, apparently tried to enter the complex tonight but turned back.

Negotiations here remained stalled amid reports of persistent fighting among a dozen inmate factions. "We are willing to die here if you make any attempt to send us back to Cuba," inmate Carlos Marrero-Gonzalez told a television crew admitted to the prison before dawn.

The prisoners torched four buildings and seized more than 70 hostages Monday, protesting a revived U.S.-Cuban agreement to repatriate about 2,500 criminals and mental patients among the 125,000 Cuban refugees who arrived in the 1980 Mariel boatlift. More hostages were seized before dawn today in a raid on the prison hospital.

The takeover here followed two days of rioting by more than 1,000 Cuban inmates at the federal detention center in Oakdale, La. They still held 28 hostages there today, but negotiations that stalled Tuesday resumed at 6 p.m. A heavy rain caused minor flooding in the compound, where many of the rebels have been sleeping outside since burning their dormitories Saturday.

Quinlan said authorities anticipate a quicker resolution at the Oakdale facility, where inmates generally had been convicted of less serious crimes than those in Atlanta, and where their leadership appeared to have "crystallized."

He said "the situation at Atlanta . . . is not as stable as I'd like to see it at this point." He declined to provide details on the Army antiterrorism specialists dispatched to help civilian authorities here.

Military officials said the specialists, flown to Atlanta from Fort Bragg, N.C., could provide sensitive eavesdropping and night-vision devices to learn what is happening inside the prison. If the inmates hurt their hostages and civilian authorities asked for more than advice, the officials said, the specialists have rehearsed storming tactics designed to minimize loss of life.

Quinlan said Attorney General Edwin Meese III "supports 1,000 percent that no decision will be made to rescue or otherwise take over the prison unless the hostages are harmed."

Meese on Monday offered a moratorium on deportations if the riots were ended immediately.

Prison and immigration officials here released little information, and federal agents maintained a tight cordon near the prison. The main source of news for inmates' relatives who keep vigil across the street continued to be police-radio scanners that relayed walkie-talkie traffic from inside the walls.

At one point, the scanners carried the voice of a hostage who identified himself as a prison guard. "Don't do anything stupid," he urged authorities. "They have me here outside, and they're going to kill us if something stupid is done. The Cubans are ready to put an end to all of us."

At about 8:50 p.m., a dozen federal agents armed with rifles appeared to try to enter part of the prison, but turned back, apparently after an inmate sentry fired on them.

The agents trotted along the front of the administration building, then moved through a space in a barbed-wire-topped fence and behind the building.

Moments later a cry that there was "a shot in the corridor" was heard on a radio band used by government agents. Shortly thereafter the agents reappeared. Later an ambulance arrived and picked up a person who appeared able to walk. It was impossible to tell whether he was one of the agents who had entered the complex.

"The guards were trying to get in here, but everything is under control," an inmate who is using the name Ciro was overheard to say by a reporter monitoring a radio scanner.

A Cuban inmate, who died Monday of a gunshot wound to the head, is the only confirmed fatality at the prison. Four inmates could be seen today combing the ashes of the prison factory in an apparent search for bodies.

According to the Bureau of Prisons, 419 inmates, including 176 Americans and 243 Cubans, have surrendered to authorities at the Atlanta facility. Around midnight tonight police radio traffic indicated that another Cuban had surrendered, but that was unconfirmed by the Bureau of Prisons.

An estimated 75 hostages were taken in the initial rioting, which began when the factory was torched. Several hostages were later released for medical reasons, but at least two dozen more were taken when inmates stormed the hospital early this morning.

Justice Department spokesman Patrick S. Korten said today that the hospital "had been cut off" since the uprising began. "We could not get to the hospital to enable the staff to get out," he said.

"For a while, the detainees let them alone . . . the problem is that for the first several days those who felt it was better to leave the hospital alone were in the ascendancy," he said. "At some point, a rougher bunch who didn't buy that decided to go in and take it over."

Outside the prison walls today, a steady stream of gawkers drove slowly past, although there was little to see. Sherry Alvarez, 37, gazed at the walls with a worried frown. Her husband of two years, Edel, 37, has awaited deportation since a month after he was arrested for shoplifting in November 1983. He later hit a county jail guard on the head with a telephone receiver.

According to a 1985 count by the Immigration and Naturalization Service, 38 of the 1,400 Cubans at the penitentiary have been incarcerated continuously since they arrived in the United States. Another 415 were convicted of violent crimes after their arrival. Most of the others had been convicted of nonviolent crimes and were ordered held pending deportation.

"I've been hoping I'd see him get on the bus," Alvarez said of her husband. "I'd been hoping the girls {other inmates' relatives} would tell me they'd seen him get on the bus."

More than 300 inmates, mostly Americans, were driven out of the prison Tuesday. Another five busloads left the prison today.

As night fell, electricity appeared to have been restored to buildings along the prison's periphery. In the parking area in front of the prison, fire trucks and SWAT teams waited. Agents with "U.S. Justice Department" printed on the backs of their windbreakers manned the outer gates. Uniformed SWAT teams patrolled, and Atlanta police waited to seal nearby streets in case of emergency.

At the Oakdale facility, there was more visible activity but no apparent progress.

"Things were a little quieter," said Ray Valdes, spokesman for the Bureau of Prisons. "I guess you could say we had another tie."

Sen. John B. Breaux (D-La.), who has been monitoring the negotiations, said the Cubans changed their demands slightly today, indicating that they would be willing to be deported to any country other than Cuba.

From the facility's perimeter, it appeared that inmates had set up their own paramilitary organization. They had constructed a shack near one of the front buildings and painted "Control" on its front.

Several makeshift guard shacks had been built from shower rods, metal, curtains and cardboard, and a few dozen detainees patrolled the grounds. They were wearing bright yellow rainsuits -- gear that had been issued to them for the Louisiana rainy season a week before the uprising.

Under several of the entranceways to buildings, inmates could be seen huddling around bonfires. They had placed buckets on the roofs to collect rainwater. Several were waving American flags.

The area's congressman, Clyde C. Holloway (R), who urged authorities Tuesday to wait out the rebels, said today that 40,000 pounds of food -- three or four weeks' worth -- had been delivered to the prison three or four days before the revolt began.

Warden J.R. Johnson said he was "still very, very optimistic" that the crisis would end peacefully, but he said there was not much movement in the negotiations today. As the seige ended its fifth day and Thanksgiving approached, several refugee-rights groups complained that federal officials were mishandling the negotiations.

Salvador Longoria, a Cuban-American lawyer from New Orleans who has represented several refugees here, said he asked federal authorities to bring Miami's auxiliary bishop, Augustin Roman, to the scene to help the talks, but the FBI rejected the idea and would not comment on the decision.

Longoria and the Rev. Roy Bourgeois, a Maryknoll priest who served six months in the Oakdale prison on a federal trespassing conviction, said that the inmates had said they know and trust Roman but do not trust the federal officials with whom they have been negotiating.Staff writers David Maraniss in Oakdale, La., and Ruth Marcus and George C. Wilson in Washington contributed to this report.