Khartoum's new ruling authorities tighten their grip on the state after ousting the former transitional government.
Sudan's army chief, Abdel Fattah al-Burhan, dismissed the public prosecutor, state TV reported on Sunday.
Burhan has relieved several officials, including diplomats, from their posts since an army takeover last week.
UN Secretary General Antonio Guterres has also urged Sudan's generals to reverse their takeover of the country.
The appeal made by the UN chief came a day after tens of thousands of people took to the streets in the largest pro-democracy protest since last week's coup.
Antonio Guterres said on Sunday that the generals should “take heed” of Saturday’s protests.
“Time to go back to the legitimate constitutional arrangements,” he said in a tweet.