Rhodesian incursions deep into this newly independent "frontline" nation are creating havoc for tens of thousands of civilian refugees from the Rhodesia war living in camps along Mozambiquc's western border.

Mozambican authorities have just asked the United Nations to step up assistance to cope with an additional 6,000 to 10,000 refugees who have reportedly fled from rearbase and transit camps belonging to the Zimbabwe People's army, the main nationalist guerrilla force, following the latest Rhodesian incursion. The guerrilla force takes its name from the African word for Rhodesia.

The plight of the Zimbabwean refugees is one of the least publicized aspects of the Rhodesian war. This is partly because they live in remote camps that are difficult to reach even in the dry season.

It also partly due to the Mozambique government's effort to keep outsiders, even international agencies like the U.N. High Commission for Refugees, from visiting the camps. No foreign relief officials, not even doctors, are stationed in the camps, according to Western diplomatic sources. Only in the past couple of weeks has Mozambism allowed reporters to visit the camps.

While the Rhodesians insist they are only hitting camps of the Zimbabwe People's Army, each raid seems to leave death and destruction among the civilian refugees as well.

It is not clear whether this is deliberate Rhodesian policy or an "accident of war." Some international refugee officials say part of the problem lies in the failure of Rhodesia's nationalists to clearly separate the civilian population from the guerrilla camps.

There are already about 35,000 refugees settled in three U.N.-assisted and Mozambican-run camps. The largest is at Dorol, about 20 miles northeast of here, housing nearly 18,000. It is a short distance from the main guerrilla camp the Rhodesians occupied and largely destroyed on Nov. 23-24.

Local authorities told three Western correspondents who were scheduled to visit Doroi last week that it was no use going now. The refugees were all hiding in the bush during the day for fear of more Rhodesian attacks, they said.

"Many have been traumatized by the attacks," explained one local official. "They don't want to talk even to us without their own leaders being present. They think we may be spies for Smith" - Rhodesian Prime Minister Ian Smith.

The refugees still return to Doroi camp at night, he said, but they have given up planting their fields just as the rainy season is getting under way. The result is expected to be a food shortage, as exists in the other official refugee camps.

The white-minority Rhodesian government has termed the November incursion - Rhodesia's biggest - a spectacular success, with as many as 3,000 casualties inflicted on the main nationalist guerrilla force.

The Mozambicans say the main victims were noncombatant women and children living in transit or reception camps.

The death toll is still mounting as more wounded refugees die in the hospital here and in the port city of Beira and in Tete City, 220 miles to the north. The latest official estimates are that about 100 refugees were killed in the Nov. 23-4 attack on the Mecombezi guerrilla camp outside this Portuguese-built colonial town and nearly 250 at another camp at Tembue in Tete Province. The number of wounded is put at 700.

The latest U.N. report on Mozambique says that 1,500 persons had died as the result of Rhodesian raids, two-thirds of them Zimbabwean refugees, as of June. The toll is now fast approaching 2,000.

The difficulties international relief officials can have working here were illustrated just after the latest Rhodesian raids. The U.N. high commissioner for refugees, E. Q. Blavo, was escorted by two government officials to Chimoio only to be barred entrance by local authorities who wanted guerrilla leaders to approve his visit first.

The United Nations is providing about $2 million in assistance to the Zimbabwean refugees this year and budgeting around $3 million for 1978. Sweden and private church groups gave another $1.4 million in aid this year.

No outsider seems to know how many civilians are located in the guerrilla transit and rearbase camps but estimates reach as high as 30,000. U.N. assistance already is being provided to about 35,000 refugees here.

Some outside observers believe the Mozambican government is not altogether happy with the presence of so many civilians in the guerrilla camps. They note that the Front for the Liberation of Mozambique (Frelimo) that now rules this nation carefully separated civilian and guerrilla populations located in Tanzania during its 10-year struggle against the Portuguese. The civilian camps were run by Tanzania and the military ones by Frelimo.

The Zimbabwe African National Union, the nationalist faction based in Mozambique, seems to prefer having the dependents of the guerrillas in camps they can continue to control directly.