Bachelet made the plea on Monday after she said her office had received reports that more than 100 protesters were killed and many more injured during an assault by Sudanese soldiers on a peaceful sit-in outside the defense ministry headquarters in the capital, Khartoum, on June 3, Presstv Reported.
The uprising in Sudan "has been met with a brutal crackdown by the security forces this month," Bachelet said in a speech at the UN Human Rights Council in Geneva.
The UN human rights chief added that the Sudanese authorities must grant her office’s monitors access to the crisis-ravaged country and allow investigation into the deadly crackdown on pro-democracy protesters.
Bachelet also urged authorities to “immediately” end shutdown of the Internet in Sudan.
Sudan's ruling military council said on Sunday that Ethiopia and the African Union (AU) should be unified in their efforts to mediate between the council and an opposition coalition on the structure of the country's transitional government.
The Sudanese military overthrew long-time President Omar al-Bashir after some four months of widespread protests against him over dire economic conditions on April 11.
Following Bashir’s ouster, the coup leaders established the so-called Transitional Military Council (TMC), presumably to run state affairs in the post-Bashir era. But the generals also moved to consolidate power and faced popular protests themselves.
Protesters camped outside the military headquarters in Khartoum for weeks to demand the ruling military council hand over power to a civilian government, before security and paramilitary forces dispersed them in a June 3 crackdown that killed tens of people.
The umbrella protest movement Alliance for Freedom and Change says 113 people were killed in the crackdown. The government puts the death toll at 61 people, including three security personnel.
Sudan's opposition groups have accused “some Arab countries” of supporting the military council in order to protect their own interests in the country.
A group of five United Nations rights experts has urged the Human Rights Council to launch an "independent investigation" into possible violations committed by Sudanese security forces against "peaceful protesters".
Bashir, who took power through a military coup in 1989, is also wanted by the International Criminal Court (ICC) over his alleged role in genocide in the Darfur region, which he denies.