Fresh gunfire has erupted overnight in the South Sudanese capital, Juba, a day after the government said it had quashed an attempted coup.
There are reports of heavy weapons being fired near the presidential palace and a military headquarters.
Several thousand people have taken refuge at two United Nations compounds.
On Monday, President Salva Kiir blamed soldiers loyal to his dismissed former deputy Riek Machar for the violence, in which at least 26 people died.
He said the clashes began when unidentified uniformed personnel opened fire at a meeting of the ruling party, former rebel force the Sudan People’s Liberation Movement (SPLM), on Sunday night.
A night time curfew is now in place and at least four former ministers have reportedly been arrested after the alleged coup. Mr Kiir said the government was in full control of the capital.
Foreign Minister Barnaba Marial Benjamin said Mr Machar was “wanted by the government” and had gone into hiding.
President Kiir sacked Mr Machar, along with his whole cabinet, in July, reportedly following a power struggle.
Mr Machar, who has said he plans to contest the presidential elections in 2015, now leads a dissident faction within the SPLM.
At least 27 people have been killed in clashes, according to Makur Korion, the Under-Secretary for Health. More than 150 others were injured in the fighting. While the government says the bodies are currently at the Juba Hospital mortuary.