Singer Stevie Wonder, saying he chose Valentine's Day to become "a conscientious criminal for world equality," was arrested at the South African Embassy yesterday during ongoing demonstrations against apartheid.

"Yes, I am guilty today," said Wonder, who was arrested along with 47 other protesters while singing "We Shall Overcome" outside the embassy at 3051 Massachusetts Ave. NW.

The 34-year-old entertainer and composer, winner of numerous Grammy Awards and other musical honors, said in brief remarks before his arrest that he was guilty of being "a conscientious criminal for world equality and against racial oppression and apartheid."

Wonder, who is blind, was accompanied during the protest by Ewart G. Abner Jr., president of the Black Music Association, who also was arrested.

They were handcuffed and placed in a police cruiser after their arrests, while other protesters, including members of Washington Area Scholars Against Apartheid, were taken from the embassy in police vans and a bus.

Since Thanksgiving Eve, when three Free South Africa Movement leaders were arrested at a sit-in, demonstrations have been held at the embassy every weekday afternoon. They are media events, designed to keep the spotlight on South Africa's apartheid policies while Congress considers proposals that would sever or curtail U.S. economic and other ties to that nation.

Wonder's participation yesterday is the latest example of how protest organizers have been able to generate and sustain interest in and press coverage of the continuing demonstrations.

They have carefully spaced out appearances by entertainers and other celebrities, hoping to spice up a protest scenario that is otherwise always the same.

Pickets begin gathering a block south of the Massachusetts Avenue NW embassy, the closest they may legally demonstrate, at 3:30 p.m.

A news conference denouncing apartheid is held at the protest site, and by 4:30 p.m. the day's preselected "messengers," wearing armbands, walk or are bused up the street to the embassy's front door.

The protesters ask to see the ambassador, are told the embassy is closed to them and reassemble on the sidewalk, where they sing "We Shall Overcome" until police lead them off in handcuffs.

By 5:30 p.m., the protesters, charged with demonstrating within 500 feet of the embassy, a misdemeanor, are being processed by police, and the other pickets have dispersed.

Most faces on the protest line change from day to day, as does the amount of press attention. Wonder's appearance, for instance, drew the largest media contingent in days.

The marchers, however, usually number between 100 to 200, and arrests have varied each time from as few as three in the beginning to more than 100 in recent days.

Randall Robinson, protest coordinator, said yesterday the demonstrations and arrests will continue for as long as necessary because, "Freedom must come at long last to South Africa.