South African warplanes flew almost 200 miles into Angola yesterday to attack a guerrilla training camp of the South-West Africa Peoples' Organization (SWAPO), according to a statement today from military authorities in Pretoria.

In a separate action, at least one South African soldier was shot dead during a six-hour clash today with Mozambican forces on that border, official statements from the two countries said.

South African authorities called the incident an "ambush" and warned that it would heighten tension, which has been high since South African forces carried out an hours-long raid on offices of an anti-South African guerrilla movement in Mozambique's capital of Maputo on Jan. 30.

The incursion into Angola yesterday is the first major raid acknowledged by South Africa on SWAPO bases in that country since the Western-sponsored peace talks between SWAPO and South Africa, in Geneva, broke down in January.

The aborted conference was aimed at ending the 15-year-old war in which SWAPO is seeking to wrest control of semi-desert South-West Africa, also known as Namibia. South Africa's presence there under an old League of Nations mandate is considered illegal by the United Nations.

Before yesterday's raid, five South African soldiers and 285 SWAPO guerrillas had been killed this year in the war, according to South African military figures.

The Geneva talks failed after South Africa objected to what it described as U.N. favoritism toward SWAPO. The United Nations was to oversee a cease-fire under the peace proposal largely initiated by the Carter administration. The initiative is presently in limbo while the Reagan administration reviews its policies in Africa.

[A State Department spokeswoman, voicing "utmost concern" over the latest raid, said, "We do not believe that there is a military solution to the conflict in Namibia. The United States supports the path of negotiations leading to a settlement of the issues and to Namibian independence."]

A delegation of Namibian political leaders who oppose SWAPO and have the sympathy and backing of South Africa are now in Washington to see government officials.

A communique from South African defense chief Constand Viljoen gave scant details of the raid on what was described as a SWAPO military base just west of the town of Lubango, formerly Sa da Bandeira.

The attack was carried out only "after repeated warnings to Angola" about the guerrilla presence in that country, Viljoen said.

Another military official said all South African aircraft involved returned safely. One newspaper here said the training camp was name Tobias Hainyeko after the first SWAPO member killed in the war.

There were contrasting versions from South Africa and Mozambique about what happened between their forces today. The state-run Mozambique news agency, AIM, said two white South African soldiers were killed during a six-hour gun battle inside Mozambique near Ponto do Ouro after about 50 South African troops, mostly black, crossed the border about 9 a.m.

In the clash that followed, South Africa sent about 150 men and two assault cars as reinforcements, AIM said. The body of one white soldier was taken to Maputo while another was recovered by the South Africans, it reported.

In response, the South African military command said one soldier was killed when he and some colleagues "unsuspectingly and probably innocently" crossed into Mozambique on a beach where there is no border marking.

"The alarming aspect of this incident is that the young men were led into an ambush and attacked without warning," the South African statement said.

"If it is the attitude of neighboring countries to attack South African soldiers who unsuspectingly and innocently wander across the border, they are heading for a serious crisis and such deeds will inevitably be viewed as deeds of open hostility," Viljoen said.

"The present development will without a doubt heighten tension on the border. That country and its undisciplined military commanders who caused this incident will have to accept reponsibility for this."