South African President Jacob Zuma traveled Wednesday to a mine where police killed 34 strikers and wounded another 78, causing outrage and eroding support for the party that has ruled South Africa since the end of apartheid.

Demands for higher wages spread to at least two other mines, raising fears the instability could inflame protests at more of the South African mines that provide 75 percent of the world's platinum. South Africa's miningweb.com Web site calls it "a possibly ominous development" that could have a "devastating effect on the South African economy as a whole with metals and minerals sales providing such a large part of the country's export income."

Thandi Modise, premier of North West Province where the platinum mines are located, warned Tuesday that the protests may spread if authorities don't deal with the massive and growing inequality gap that has many South Africans feeling they have not benefited in the 18 years since black majority rule replaced a racist white minority government. South Africa has become the richest nation in Africa but still has more than 25 percent unemployment – nearer 50 percent among young people. Protests against shortages of housing, electricity and running water and poor education and health services are an almost daily affair.