UN High Commissioner for Human Rights Volker Turk said on Wednesday that a full-scale conflict is underway in Sudan, and the impact on the humanitarian situation in the country has been "catastrophic". 

During a meeting of the UN Security Council, Turk commented, "The latest country to move toward full-blown conflict is Sudan. The human rights impact of the current fighting has been catastrophic. It is heartbreaking."

He added that the country's future relies on the rate of confidence of the people in the Sudanese institutions.

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The Sudanese Ministry of Health announced that the casualties of the conflict have steadily increased since the conflict broke out in mid-April. The ministry estimated that more than 550 have been killed and approximately 5,000 have been injured. 

"In all hospitals in the provinces of Sudan, a total of 550 deaths and 4926 injured were recorded," the ministry announced in a statement on social media. 

This comes after UN Spokesperson Stephane Dujarric confirmed on Monday that UN Secretary-General Antonio Guterres has spoken to both Sudanese rival generals over the phone "at different times" and that "he will do whatever needs to be done."

He added that Guterres has the phone "glued to his ear" amid warnings that more than 800,000 people could flee fighting in Sudan, where gun battles and explosions again shook the capital in violation of the latest truce agreed between the warring generals.

According to the Ministry of Foreign Affairs of South Sudan, a truce was agreed upon from May 4 to May 11 on Tuesday by the leaders of the Sudanese military and the Rapid Support Forces (RSF).

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The chaos and bloodshed, now in their third week, have sparked a mass exodus of tens of thousands of Sudanese to neighboring countries including Egypt, Chad, and the Central African Republic. Millions of Sudanese around the capital and beyond have sheltered in their homes with dwindling food and water and frequent power cuts.

"Warplanes are flying over southern Khartoum and anti-aircraft guns are firing at them," said one resident, while another witness told AFP that he was also hearing "loud gunfire".