PORT-AU-PRINCE, HAITI, NOV. 29 -- Haiti's first free national elections in 30 years were suspended today, and the military government dissolved the independent electoral council after armed allies of the deposed Duvalier dictatorship unleashed a reign of terror across the capital. Armed gangs shot or hacked to death at least two dozen Haitian voters and one foreign journalist and destroyed polling places and radio stations.

Throughout last night and this morning, gangs including remnants of the Ton-Tons Macoutes, the disbanded Duvalier paramilitary force, rampaged freely through city streets in civilian cars, armed with submachine guns and machetes. At times they fired randomly at passers-by; at other moments they attacked with bullets and grenades, aiming to kill voters, journalists, elections officials and foreign observers.

There was only a light presence of regular Army troops in the streets and victims of the violence reported several incidents in which the Army appeared to overlook or actively assist the murderous forays. During weeks of antielection violence, apparently by the remnants of the Duvalier security apparatus, the Army abstained from intervening until enraged citizens last week formed watch committees to counter the attacks.

Following a night of violence, the president of the electoral council, Ernst Mirville, announced at 9 a.m., by telephone from a hideout, that the election was postponed until further notice. Most of the nine electoral council officials and many candidates went into hiding early today.

Mirville described electoral officials as "walking dead men" because of the danger he said they face.

{The Reagan administration, which had given $8.1 million in aid for the election, blamed the violence on supporters of Duvalier and cut off all nonhumanitarian aid to Haiti. Details, Page A26.}

In a decree published at about 3 p.m., the ruling National Government Council headed by Gen. Henri Namphy abolished the electoral council, charging that it had ignored the constitution and had been manipulated by foreign interests.

The collapse of the election seemed to put an end to Reagan administration hopes that the government would lead Haiti to a prompt, orderly vote -- yielding popular leaders who could restore some peace to an anarchic nation.

However, in a nationally televised address tonight, Namphy said the government will take direct control of the electoral process and keep to a constitutionally mandated schedule that calls for the inauguration of a new president on Feb. 7, 1988. He condemned the day's violence. He did not say when new elections would be held.

Namphy's takeover of the electoral process after his government had tolerated the antielection violence gave an impression that he had allowed terrorists to scuttle the vote and vindicate his position in a five-month-old power struggle with the independent electoral council. Since the downfall of dictator Jean-Claude Duvalier 21 months ago, the military-led government has tolerated continued influence of the Ton-Tons Macoutes, who were formally disbanded but not forced to give up their arms.

The official U.S. delegation of observers appointed by President Reagan was evacuated from Haiti in its U.S. government aircraft at midday.

The violent spree in Port-au-Prince began late last night as bands of gunmen in cars roamed the streets shooting at random and setting fire to three precinct electoral offices and a gas station. One giant blaze lit the sky over Port-au-Prince for almost an hour.

Three radio stations that broadcast news were sprayed with gunfire. The transmitter of a fourth, widely heard station, the Catholic Church's Radio Soleil, was crippled with grenades and firebombs by a squad of 16 uniformed soldiers, according to its director, Father Hugo Trieste. Trieste said the soldiers also burned the nearby homes of two of the station's night watchmen, one of whom suffered critical burns and gunshot wounds.

According to witnesses, about 30 Army soldiers also launched a carefully coordinated predawn assault with automatic rifles and hand grenades on the home of electoral council treasurer Alain Rocourt. Rocourt's family escaped.

"We saw whole handfuls of shells and seven used hand-grenade clips," said an elections observer, the Rev. Allan Kirton of the Caribbean Conference of Churches. Kirton and other religious election observers were inside Rocourt's house at midmorning when troops returned to shower it again with gunfire.

The shootings intensified after the polls opened in Port-au-Prince at 6 a.m. At the Argentine School in downtown Port-au-Prince, about 100 voters were in line around 7:30. About 50 men with rifles and machetes burst into the courtyard and fired bursts from their automatic weapons.

Witnesses said some Ton-Tons Macoutes finished off with machete slashes voters who lay screaming in pain from their bullet wounds. When journalists first arrived they found the courtyard awash with blood and 10 mutilated bodies piled in a corner. At least 14 Haitians died at the school.

Dazed voters stayed behind to try to help four wounded voters who were bleeding badly. But as journalists concentrated, a gray jeep carrying helmeted Army soldiers drove up to the door and the troops opened fire again into the polling place courtyard, according to Jean-Bernard Diederich, a free-lance photographer working for Time magazine.

Diederich and other journalists fled with bullets whistling around them. It could not be determined if more voters died in the later round of shooting at the school.

At a nearby polling place, also in a school, gunmen described by witnesses as Ton-Tons Macoutes stormed in while photographers were taking pictures of the balloting. Dominican cameraman Carlos Grullon of the Santo Domingo television station Rahintel was shot at close range and died at midday, a colleague, Pablo Nunez Patino, said. A British photographer, Geoffrey Smith, was wounded by the gunfire.

Javier Carillo, a Mexican, and Alfredo Mejia, a Salvadoran, both members of an ABC News camera crew, and a Haitian driver, Franklin Ver, were also shot. ABC correspondent Peter Collins said the three men were hiding, crouched behind a wall, when a gunman with a heavy-caliber pistol followed them, "took careful and deliberate aim" at close range, and fired.

Voice of America correspondent Greg Flakus and three other journalists were chased from a polling station by pistol-firing Ton-Tons Macoutes. They were forced to hide for three hours this morning in a Port-au-Prince neighborhood while the Ton-Tons Macoutes searched several houses tracking them. "They were trying to kill us -- there's no question about that," Flakus said.

Elections observers also reported that ex-Macoutes attacked at least three Roman Catholic churches in the capital, killing at least two Haitian worshipers inside. "There has been a planned assault on the churches," said Rev. Leslie Griffiths, another member of the Caribbean Conference of Churches delegation.

In the Sacre Coeur church, which was also a polling station, Ton-Tons Macoutes interrupted the morning mass and beat two women with the butts of machetes. They climbed on the altar and destroyed several altar pieces, the parish priest, the Rev. Nicholas Christian, said. The Catholic Church played a key role in the Feb. 7, 1986, ouster of the Duvalier dynasty and has strongly supported the elections.

The terrorist attacks accomplished what many observers believed was their goal: to move the government to impose its own control and stop the elections.

Many Haitians in the capital remained in voting lines for several hours this morning despite the violence, before the election was called off. Throughout the city, observers saw Haitians determined to vote and frustrated and frightened when the balloting was stopped.

"I'll wait all day if I have to. If there's an election, I'll vote," said a 51-year-old pharmacist who, out of fear, gave only his first name, Vital. He was waiting at a polling station that had, by 8:30 a.m., already been sprayed twice with gunfire.

An independent American elections observer, former ambassador Robert White, said the vehicle he was traveling in was sprayed with gunfire from a passing jeep. Later in the morning White was at a polling station that was fired on by Ton-Tons Macoutes. White said a Haitian elections official delivered the ballots to the station in the midst of the gunfire.

On one avenue, White said he saw Army troops remove a rock barricade put up by neighborhood people and allow a band of Ton-Tons Macoutes to pass. "The Army totally abandoned its responsibility," White said. "It turned the streets over to the Macoutes."

The electoral council and the government exchanged accusations. Mirville, the electoral council president, said, "The government council is completely responsible for the failure of the election. They humiliated and ignored us." He blamed the violence on "criminals who seem to be sure of their impunity."

The Government Council said the electoral council "showed contempt" for the law, was not impartial and "invited foreigners to meddle in Haitian affairs." The United States, France and Canada provided substantial elections aid.