The Rhodesian defense force announced yesterday that it had "neutralized" 10 guerrilla bases belonging to Robert Mugabe's Zimbabwe African National Liberation Army in a massive two-day air operation into neighboring Mozambique.

The military communique, issued in the Rhodesian capital of Salisbury late last night, said only that the "self-defense" operations had ended with one minor casualty. No further details were given.

Meanwhile, a military spokesman in the Mozambican capital of Maputo confirmed the Rhodesian raid, saying that 12 people had been killed and 110 wounded when targets, including a school, had been hit in the Manica and Tete provinces of Mozambique.

The spokesman said the attacks began about 9:30 a.m. Sunday morning. The Rhodesian planes with-drew after Mozambique forces reacted to the attack in the Gondola area of Manica Province, but returned to bomb the area about 5 1/2 hours later, he said.

A Rhodesian military spokesman refused to expand on the brief military communique or to confirm what the Mozambican spokesman said.

The communique was considered unusual in that it failed to list the number of guerrillas killed or to describe the quantities of arms captured or destroyed. In previous major attacks into Mozambique, the military command has been quick to claim success in those terms.

(Reuter reported from Salisbury that top Rhodesian military personnel, including Gen. Peter Walls, chief of the armed forces, were understood to have entered Mozambique during the rid).

It is believed the principal targets of the raid were training camps of Mugabe's amy, where thousands of guerrillas are thought to be preparing for an offensive into Rhodesia.

During a similar strike on Mugabe's forces at Chimoio and Tembue more than 60 miles inside Mozambique last November, the Rhodesians claimed that they killed 1,200 guerrillas, but Mozambican authorities claimed many of the dead had been civilian refugees. The latest raid is the fifth acknowledged strike into neighboring Mozambique in the course of the six-year-old bush war.

The weekend raid was the second time military authorities have acknowledged an operation into a neighboring country since the biracial transitional government of Prime Minister Ian Smith and three internal black leaders was formed in Salisbury last March. On March 6 Rhodesian forces entered Zambia and killed 42 guerrillas of Joshua Nkomo's Zimbabwe People's Revolutionary Army.

This latest raid no doubt was intended to demonstrate that the transitional government, which is meant to lead the country until black majority rule is established the end of this year, still has sufficient military muscle to meet the steadily escalating activity of both Nkomo's and Mugabe's guerrilla forces.

Since Smith was joined by his three colleagues - Bishop Abel Muzorewa, the Rev. Ndabaningi Sithole and Chief Jeremiah Chirau - war casualities, most of whom are black civilians, have increased to an average of more than 100 a week.

But the most recent raid is also seen as an attempt to prevent a disruption of what the military authorities claim is slow but steady progress in persuading many of the guerrillas to accept an amnesty offered by the government May 6.

According to Rhodesian military and government sources, Mugabe's forces had been given orders to assassinate guerrilla leaders among them who were sympathetic to accepting the amnesty and giving support to the internal settlement. Smith has said in interviews that "killer squads" were being sent into Rhodesia for this purpose and also to attempt to assassinate the three black internal leaders.

The first military communique on the latest raid issued Sunday claimed that "there is clear evidence that the cease-fire exercise is beginning to work within Rhodesia "and" nothing must be allowed to prejudice this encouraging internal development." This was given as a reason for what the military release termed a "self defense" operation.

Finaly, the raid was apparently intended to boost morale among the population, particularly among the whites, who have been disheartened by the lack of a cease-fire and by continued attacks by guerrillas on both black and white civilians.