When Percy P. Qoboza was a Nieman fellow here two years ago, he justified his newspaper's emphasis on sensational rather than political news by saying his responsibility as an editor was to keep the largest black paper in South Africa from being closed down.

But when he returned to his paper, the World, in June 1976--the month the riots broke out in Soweto and other black townships--Qoboza apparently changed his mind.

More and more, Qoboza and his paper became the voice of the black community, taking a clear stand in the struggle against the white minority regime, Obed Kunene, editor of a smaller against the white minority regime, Obed Kunene, editor of a smaller black South African paper and a Nieman fellow this year, said this week.

So when the South African police cracked down early Wednesday morning on even moderately anti-apartheid groups throughout the country, Qoboza and his paper were two primary targets.

Qoboza had said when he was here that getting to know Americans would partially protect him from South African repression, and, to some extent at least, his theory seems to have been correct.

Expressions of outrage at his arrest--as well as a the arrests of 50 other prominent black leaders--have filled the U.S. media this week, and numerous campaigns to protest the crackdown have been organized.

The Harvard-Radcliffe Southern African Solidarity Committee, a group of concerned students, has asked the University to reconsider its holdings in companies that operate in South Africa in light of the recent police action.

President Bok could not be reached for comment this week.

But James C. Thomson, curator of the Nieman Foundations for Journalism, was not mincing words. "With this nationwide, brutal suppression of dissent," he said Wednesday, "the illegitimate Pretoria regime moves far toward terminating its last cosmetic pretence to democracy--namely, a free press."