The two neighboring countries have much in common, including similar examples of nation-building, beginning in the 1990s, after years of conflict, the (Johannesburg) Times noted, but tensions have been simmering for the past several years.
The killing in December of a Rwandan intelligence officer in Johannesburg, and the death of a former Rwandan army chief, again in Johannesburg, has ratcheted up tensions between the two countries, the Times said.
Much of the tension, the report said, comes from suspicion on the part of South Africa and other African countries that Rwandan President Paul Kagame has had a role in the M23 rebellion that has disrupted Democratic Republic of Congo.
The killings and attempted killings of opposition leaders and Kagame's enemies have resulted in a diplomatic crisis, the Times said.
After the Johannesburg shooting of a Kagame opponent four years ago, South Africa's ambassador to Rwanda was recalled, a strong message from South Africa that it disapproved of illegal Rwandan activity on its soil.