Santiago de Cuba, April 2 - Fidel Castro, rebel leader, has succeeded in paralyzing land communications between Oriente Province and the rest of Cuba. But army troops remain in full control of Santiago de Cuba and the city is quiet tonight.

Government planes strafed the Oriente village of El Aguacate this morning, killing three civilians, according to reports reaching Santiago de Cuba. El Aguacate is forty miles northwest of Santiago de Cuba, on the central highway to Havana.

Reports said that the air attack was launched after an army convoy had been ambushed by rebels near the village. There were no reports on rebel or army casualties.

This capital of Oriente, a hotbed of revolt against President Fulgencio Batista, can be reached from Havana only by air. Railroad and highway traffic has been halted completely. Telephone service is disrupted most of the time.

Paralysis of communications is the first phase of Señor Castor's "total war" plan against the Batista regime. Starting yesterday, rebels were instructed to fire without warning on moving vehicles and trains.

Eight passengers who alighted last night from Havana drove to town over three miles of lonely roads without running into an ambush. But tonight's flight was canceled. Cubana Airlines also suspended all flights between Santiago de Cuba and other Oriente cities yesterday after rebels fired on a plane yesterday morning near Baracoa.

The city is strangely quiet. It is not a pleasant stillness. By night the narrow downtown streets, normally crowded until midnight, are deserted and the houses are shuttered.

By day the shops are open, but they are empty of customers. Fearing outbreaks of shootings, most of the people prefer to stay home.

Most of Santiago de Cuba's food is trucked from provincial farms along the central highway. Unless Government troops keep this highway open the city faces hungry times.

There is no immediate threat of hunger. Although the city market was running short on everything except tomatoes today, most families have been hoarding food supplies in anticipation of a general strike.

United States citizens in Santiago de Cuba say the city had been unusually calm for more than a week. Order is being maintained by heavy reinforcements of troops and police. Troops have been posted on the roofs of buildings near the United States Consulate and at other strategic points.

Of the 2,000 United States citizens living more or less permanently in Oriente Province, slightly more than sixty women and children have returned to the United States during the last two weeks. Their withdraw has been entirely voluntary. The United States Embassy in Havana so far has not even alerted United States citizens to the possibility of danger.

Embassy officials have studied reports of rebel sabotage in factories and rebels burnings of sugar cane fields and have found no pattern to indicate that properties of United States citizens or concerns were being singled out for destruction.

Some observers believe that Señor Castro has let a favorable psychological moment for all-out revolution slip by. That moment came two weeks ago when the Batista Government again suspended constitutional guarantees and reverted to press censorship.

HAVANA, Cuba, April 2 - Rebels in Oriente Provence were reported today to have intensified sabotage and attacks on military posts.

Censorship has blacked out news from the interior provinces. Only a few reports get through concerning the activities of the rebels under the leadership of Señor Castro, who yesterday started his "total war" in an effort to overthrow the Government of President Batista.

Heavy fighting was said to have occurred at Baracoa, on the eastern tip of the island, with rebels attacking and capturing the military post there. Reports said a considerable number of soldiers were killed, wounded or taken prisoner.

Camp Columbia, the army headquarters near Havana, announced that twelve rebels had been killed in an encounter this morning at Rio Cauto in Oriente Province.

Reports said a band of rebels had attacked Campechuela, on the south coast of Oriente Province. Two of the band were said to have been killed.

Rail and Bus service in southern Camaguey Province has almost stopped.

Rebels are said to be firing on trains and on all vehicles seen on the roads. One person was killed by a fusillade yesterday.

Trains leaving Havana for the eastern part of the island during the last two days have halted at Camaguay. Railway employes are refusing to take the trains into Oriente Province because of the rebel activity.

The daily commercial plane arriving at Baracoa yesterday was fired on and did not land. The plane to Manzanillo also did not land there because the pilot saw rebels fighting near the airfield. Army planes bombed rebel positions for several hours today.

Trujillo Sends Weapons

HAVANA, April 2 (UP) - Generalissimo Rafael Trujillo, Dominican Republic strong man acting on an "emergency request" from President Batista has rushed five planeloads of arms and ammunition to the Cuban army, it was learned today.

The weapons apparently were sought as a replacement for a shipment of about 2,000 Garand rifles ordered from the United States but blocked in New York by a sudden State Department ruling March 11.