South Africa warned Rwanda on Wednesday that it would not allow its territory to be used for "illegal activities", following Pretoria's expulsion of Rwandan diplomats linked to attacks on South African soil against Rwandan exiled opposition members."As the South African government, we want to send a very stern warning to anybody, anywhere in the world, that our country will not be used as a springboard to do illegal activities," Justice Minister Jeff Radebe told a news briefing, referring to the diplomatic row with Great Lakes state Rwanda.