DUBLIN >> South Sudan government troops violated the country’s latest cease-fire just hours after it began at midnight, the armed opposition claimed today, while a government spokesman accused the rebels of attacking instead.

The competing claims indicated a shaky start to the latest attempt at ending a devastating five-year civil war that has killed tens of thousands and created Africa’s largest refugee crisis since the 1994 Rwandan genocide. Millions are near famine and aid delivery is often blocked in one of the world’s most dangerous countries for humanitarian workers.

President Salva Kiir and rival Riek Machar, Kiir’s former deputy, had agreed on the “permanent” cease-fire earlier in the week in neighboring Sudan after their first face-to-face talks in nearly two years. They then ordered their supporters to observe it.

Opposition spokesman Lam Paul Gabriel said government forces and Sudanese rebel militias launched a “heavy joint attack” in Mboro, Wau County in the northwest around 7 a.m. today, arriving in armored personnel carriers, trucks and Land Cruisers.

“The fight is still ongoing as I write,” Gabriel said, calling on the U.N. peacekeeping mission and cease-fire monitors to investigate. The opposition reserved the right to self-defense, he added.

“This is disappointing that even when their president and commander-in-chief Salva Kiir declares a cease-fire, the regime’s forces still violate it,” Gabriel told The Associated Press. “There is the possibility Salva Kiir is not in control of his forces or he doesn’t want peace to come.”

South Sudan government spokesman Ateny Wek Ateny told the AP that the opposition attacked instead.

“They have a loose leadership; they’re not being controlled by anyone. The people of South Sudan should be given a chance to lead a peaceful life, and the army is observing the order of the president. It’s very sad,” Ateny said.

The previous cease-fire in December was violated within hours, prompting a new push by the international community to threaten U.N. and regional sanctions against those blocking the path to peace.

This time, Kiir and Machar had faced a possible U.N. arms embargo and sanctions if fighting didn’t stop and a political deal wasn’t reached by today.

The rapid cease-fire violations are “a tradition, not because the two principals are not willing to put their words into reality but because they mostly are not in direct control of their forces,” South Sudanese activist and analyst Jon Pen de Ngong told the AP. Implementation is weakened because not all armed forces are involved in the negotiations, he said.

Both sides have been splintering, with the opposition breaking into multiple armed groups and high-level officials leaving the government in frustration amid accusations by watchdog groups that some decision-makers choose to profit from the war instead of pushing for peace.

Only financial and legal pressure on such leaders “could possibly alter current calculations that favor war, instability and chaos over peace, democracy, and the rule of law,” John Prendergast, founding director of the Enough Project, which focuses on the corruption behind Africa’s conflicts, told the AP.

Wary observers inside and outside South Sudan, including the warring sides, had approached the latest cease-fire with cautious optimism at best. A joint statement by the United States, Britain and Norway warned that effects of the halt in fighting must be seen on the ground: “It must lead to … an end to the horrendous abuses endured by civilians at the hands of security forces.”

Both sides have been accused of abuses including gang-rapes, sometimes along ethnic lines.

The latest talks between the rivals have yet to agree on a power-sharing deal, as the government has rejected the idea of Machar again becoming Kiir’s deputy. The civil war broke out between supporters of Kiir and his then-vice president Machar in late 2013, just two years after South Sudan won independence from Sudan.

A 2015 peace agreement brought back Machar as vice president but the deal collapsed in July 2016 when fresh fighting erupted in the capital, Juba, with Machar fleeing the country on foot through the bush into Congo.