South Sudan's President Salva Kiir (C) arrives during a peace signing meeting attended by leaders from the region in Ethiopia's capital Addis Ababa, August 17, 2015.  REUTERS/Tiksa Negeri

This post has been updated

As South Sudan missed another deadline to sign a peace agreement that would end its civil war this week, President Salva Kiir issued what appeared to be an ominous warning to journalists in the country.

"The freedom of press does not mean that you work against your country," Kiir said during a news conference Sunday at an airport in the South Sudanese capital of Juba, Radio Tamazuj reports. "And if anybody among them does not know this country has killed people, we will demonstrate it one day on them."

On Thursday, Kiir's comments took on a new significance when a South Sudanese journalist was shot dead by unknown gunmen. Colleagues say that Peter Moi, a reporter with the New Nation newspaper, was killed as he left his offices in Juba. "This was an intentional killing," said Oliver Modi, chairman of the Union of Journalists of South Sudan, told Agence France Presse.

Kiir's comments had already drawn condemnation from the Committee to Protect Journalists, who viewed the comments as a threat against South Sudanese journalists who had criticized Kiir's failure to reach a peace deal and published allegations of corruption. "The leader of any country threatening to kill journalists is extremely dangerous and utterly unacceptable," CPJ East Africa Representative Tom Rhodes said in a statement. "We call on President Salva Kiir to retract his comments immediately."

Critics say that South Sudan's government has been cracking down on the press recently. According to Voice of America, a number of South Sudanese media outlets, including the Citizens newspaper, a leading English-language publication, have been ordered by the government to cease publication. At least five journalists had already been killed this year due to their work, according to CPJ research, shot by unidentified gunmen as they traveled through Western Bahr al Ghazal state.

"Today it is Peter, tomorrow is someone else," Modi told AFP. "We are being taken one by one."

South Sudan is one of the world's youngest countries, having gained independence from Sudan in 2011 after years of civil war. In 2013, however, a new civil war was sparked after Kiir accused his former deputy Riek Machar of planning a coup. During this new conflict there have been a number of accusations of human rights violations, with a report by the United Nations Mission in South Sudan (UNMISS) in June accusing government soldiers of gang-raping girls and then burning them alive in the northern state of Unity.

Kiir had refused to sign a peace agreement with Machar in Ethiopia on Monday, telling mediators that he needed more time. Eric Reeves, a Smith College political scientist who studies South Sudan, said that Kiir's comments about journalists appeared to be reflection on his situation. "He is increasingly overwhelmed by the challenges he faces, his health, and total exhaustion," Reeves said.

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