Sudan's security agency seized the print run of an  independent daily on Tuesday, its editor told Agence France-Presse, the day after confiscating nearly all the country's titles without giving an explanation.

National Intelligence and Security Service (NISS) agents seized all copies of al-Tayar from the printer in the early hours, editor Osman Mirghani said.

Sudanese security officers seized the print runs of 13 newspapers on Monday in one of the most sweeping crackdowns on the press in recent years, a media watchdog said.

The National Intelligence and Security Service seized copies of the dailies -- which included pro-government as well as independent titles -- "without giving any reasons," Journalists for Human Rights said.

Sudanese army troops raped more than 200 women and girls in a Darfur town last year, in a brutal attack that should be investigated as a crime against humanity, Human Rights Watch said Wednesday.

In a 48-page report, the U.S.-based rights organization cast doubt over Khartoum's repeated denials that a mass rape took place in October in the town of Tabit. 

U.N. Secretary General Ban Ki-moon on Tuesday accused South Sudan's leaders of putting their own interests above those of their people after they failed to reach a power-sharing deal.

President Salva Kiir and rebel leader Riek Machar signed yet another ceasefire agreement late Sunday following four days of talks in Ethiopia, but they did not address the core issues behind the 13 months of fighting.

Two Russian men working as U.N. contractors in Sudan have been kidnapped in the country's Darfur region, officials said on Tuesday.

The men were employees of UTair, one of Russia's largest airlines, and were in Sudan on a contract for the U.N. mission in the country, UNAMID, the company said in a statement.

Six Bulgarian contractors for the U.N. World Food Program (WFP) who were held for a week by Sudan rebels were freed on Sunday, the Bulgarian foreign ministry said.

"The operation for liberating them ended. The six are in a safe place," ministry spokeswoman Betina Zhoteva told AFP.

Fourteen candidates have registered to run against Sudan's Omar al-Bashir in a presidential vote in April, the country's electoral commission said on Tuesday.

"The electoral commission has received a total of 15 candidacies for the post of the president of the republic," commission head Mokhtar al-Assam told reporters.

A Sudanese warplane deliberately targeted one of the few hospitals operating in South Kordofan state, where ethnic minority rebels have been fighting government troops, an international medical charity charged Friday.

Two people were wounded in the Tuesday raid in Frandala in the Nuba Mountains, where rebels of the Sudan People's Liberation Movement - North (SPLM-N) have been fighting since 2011, Medecins Sans Frontieres (Doctors Without Borders) said.

Sudan's electoral body Thursday pushed back the deadline for applications to run in presidential and legislative polls in April, saying just two candidates have so far won approval to stand.

One of the applicants was President Omar al-Bashir, 71, who is seeking to extend his 25-year rule in the April 13 election that he is widely expected to win, with opposition parties saying they will boycott.

Captured Lord's Resistance Army rebel chief Dominic Ongwen was handed over Wednesday to African Union troops to be sent to trial at the International Criminal Court for crimes against humanity, Uganda's army said.

Ongwen, who surrendered last week and was in the custody of U.S. special forces in the Central African Republic, has been sought by the ICC for almost a decade to face charges including war crimes, murder, enslavement, inhumane acts and directing attacks against civilians.