Both sides of South Sudan’s conflict are boosting their weapon arsenals in violation of a peace deal signed in August, United Nations experts said, BBC News reported Thursday. The experts, who monitor United Nations sanctions on South Sudan, said human rights violations -- including murder and rape -- have persisted, signaling that the tenuous peace deal reached last summer could collapse.

At least seven ceasefires have been broken since the country spiraled into a bloody conflict in December 2013, which has resulted in thousands of deaths and millions of civilians displaced. A 15-member Security Council warned last summer that it was ready to impose an arms embargo if the recently reached peace deal were to fail. Experts said they were still investigating the flow of arms into South Sudan and would provide further details shortly.

South Sudan refugees Internally displaced persons queue to register at a refugee camp in South Sudan's Unity State, Feb. 27, 2015. Photo: Charles Lomodong/AFP/Getty Images

The experts also accused both sides of "persistently failing to implement a permanent ceasefire and failing to agree meaningfully to security arrangements that are requisite for the establishment of the transitional national government." They further accused President Salva Kiir of undermining the peace deal’s “power-sharing formula” by increasing the number of states from 10 to 28 and said border demarcation has long been a driver of violence.

South Sudan, the world’s youngest country, has been gripped by violence since December 2013, when Kiir accused former Vice President Riek Machar of attempting to stage a coup against him. The country has since broken down along ethnic fault lines, prompting a conflict that has led to one of the worst humanitarian crises in the world. The U.N. warned last month that some 30,000 people faced death by starvation, and tens of thousands more were on the brink of famine. 

The government continued targeting civilians in the Unity state, an oil rich northern region, as human rights workers reported more than 50 rapes in October. The government was also accused of opening fire at fleeing civilians, burning houses and abducting women and children, Reuters reported. Nearly one in five South Sudanese have been displaced by the current conflict.