Riek Machar arrested: Is South Sudan headed for civil war?

(FILES) South Sudanese President Salva Kiir (L), South Sudan's opposition leader Riek Machar (R) and Mohamed Hamdan Daglo (C)"Hemeti", Sudan's deputy head of the Transitional Military Council, hold hands together as they speak to media after their peace talk at the State House in Juba, South Sudan, on December 17, 2019. (Photo by Majak Kuany / AFP)

A fragile peace deal in South Sudan was collapsing on Thursday after the arrest of First Vice President Riek Machar, long-time rival to President Salva Kiir, threatened to throw the country back into war.

A convoy of 20 heavily armed vehicles entered Machar's residence in the capital Juba late on Wednesday and arrested him, according to a statement issued by a member of his party-a dramatic escalation of a conflict that has been building for weeks in the world's youngest country.