Sudan released nine medics from Doctors Without Borders (MSF) on Tuesday, the aid group said.
The medics were detained as they were making their way back to their office from a hospital, according to the organisation.
"MSF's emergency medical teams are working in Khartoum to support the health authorities with their response to injuries from ongoing protests and Covid-19," the statement said.
Among those arrested were staff members from both Sudan and other countries, according to the pro-democracy Central Committee of Sudan Doctors.
Sudan has been rocked by protests calling for civilian rule since an October 25 military coup led by General Abdel Fattah Al Burhan.
The military takeover derailed a power-sharing transition between the military and civilians that had been painstakingly negotiated after longtime autocrat Omar Al Bashir was ousted in 2019.
The crackdown on anti-coup demonstrations has left at least 76 people dead and hundreds wounded, according to the doctors' committee.
Hundreds of people have also been rounded up in the crackdown, including pro-democracy activists.
On Saturday, a leading women's rights campaigner, Amira Othman, was arrested following a raid on her home in Khartoum, according to a statement by the "No to Women's Oppression" initiative that she leads.
Other activists from the "resistance committees", informal groups which have been instrumental in organising the anti-coup protests, were also detained late Sunday, according to members who requested anonymity because they feared reprisals.
Crackdown slammed by US
The US has slammed the protest crackdown. On Tuesday, the US Bureau of African Affairs said Sudan's military leaders had committed to dialogue to resolve the crisis in the country during a visit last week by senior US diplomats to Khartoum.
"Yet their actions – more violence against protesters, detention of civil society activists – tell a different story, and will have consequences," the bureau said on Twitter.
US special envoy for the Horn of Africa, David Satterfield, on Tuesday met in Cairo with Egypt's Foreign Minister Sameh Shoukry, who reiterated his country's support for a UN-led dialogue between Sudanese factions.
Sudan is one of the world's poorest countries and has seen vital foreign aid cut as part of the international community's condemnation of the coup.