JUBA (AFP, REUTERS) - Both South Sudan's president and vice-president have ordered a ceasefire on Monday after a new day of heavy fighting in the capital Juba that sent thousands of people fleeing and threatened a return to civil war.
President Salva Kiir's ceasefire order on Monday evening raised hopes of an end to four days of deadly fighting between the army and ex-rebels.
"The president has reiterated his commitment to the continued implementation of the (peace) agreement in letter and spirit, and thus issues an order of cessation of hostilities with immediate effect," Information Minister Michael Makuei said on state television.
Vice President Riek Machar also reciprocated by ordering his SPLA army forces to halt fighting, he told the independent Eye Radio. "The president has declared a unilateral ceasefire, I want to reciprocate the declaration of unilateral ceasefire," he told the radio, saying he had ordered it to come into effect at 8pm (1am Singapore time), two hours after the deadline Kiir had set.
Monday had witnessed some of the heaviest fighting between the two sides, after clashes erupted on Thursday.
The United Nations had expressed deep alarm over days of violence between the army and ex-rebels, which has left several hundred people dead and threatens the young nation's shaky peace.
The UN Mission in South Sudan (UNMISS) said "more than 7,000 people" had sought shelter at two compounds in Juba while fighting was also reported in the south-eastern town of Torit where thousands fled to a UN base.
Eight people have been killed and 67 injured at the UN's so-called "Protection of Civilian" sites in Juba since Sunday.
"UNMISS compounds are caught directly between the fighting and continue to sustain impacts from small arms and heavy weapons fire," UNMISS said in a statement.
Intense battles were fought throughout Monday with tanks and helicopter gunships deployed and artillery and mortar fire heard in parts of the city.
Witnesses reported "very, very heavy fighting" in Juba with residents barricading themselves inside houses and aid workers holed up in bunkers while the US embassy warned of "serious fighting between government and opposition forces".
The only civilians on the streets scurried for shelter during lulls in fighting.
The current fighting between soldiers loyal to Kiir, a member of the Dinka tribe, and former rebels backing Machar, a Nuer, was triggered by a deadly altercation at a checkpoint on Thursday night.
That was followed by hours of violent confrontations on Friday evening that left "over 300 soldiers" dead, according to Makuei.
After a pause on Saturday - South Sudan's fifth anniversary of independence - battles began in earnest on Sunday morning, continuing throughout the day in several parts of the city before subsiding overnight and resuming Monday.
It is unclear how many have been killed in the fighting since Sunday that has focused on the Jebel and Tongping areas of the city.
China, once the biggest buyer of South Sudan's oil, expressed serious concern over the flare-up which led to the death of a Chinese peacekeeper.
The clashes are the first between the army and ex-rebels in Juba since Machar returned to take up the post of vice president in a unity government in April.
The violence marks a fresh blow to last year's peace deal which has failed to end the civil war that broke out in December 2013, when Kiir accused Machar of plotting a coup.
The war has been characterised by rape, ethnic massacres, attacks on civilians, the use of child soldiers, pillage, widespread destruction of property and displacement of the population.
The Security Council on Sunday pressed South Sudan's neighbours to help end the renewed fighting by offering extra peacekeepers.
United Nations Secretary-General Ban Ki-moon urged the Security Council on Monday to impose an arms embargo on South Sudan, sanction leaders and commanders who are blocking the implementation of a peace deal and fortify a UN peacekeeping mission.
"We desperately need attack helicopters and other material to fulfill our mandate to protect civilians," Ban said. "I also urge all countries contributing to (the UN mission) UNMISS to stand their ground. Any withdrawals would send precisely the wrong signal, in South Sudan and across the world."
South Sudan has seen more fighting than peace since independence in July 2011. The August 2015 peace deal was supposed to end the conflict but fighting has continued despite the establishment of a unity government.
Tens of thousands have died in the violence, with close to three million forced from their homes and nearly five million surviving on emergency food rations.
The humanitarian crisis has unfolded alongside an economic one with the currency collapsing and inflation spiralling out of control. The country's mainstay oil industry is in tatters and regional towns have been razed.