CPJ said that Quintal, a former editor of South Africa's Mail & Guardian newspaper, and Mumo were legally in Tanzania "on a reporting mission" when they were detained.
"We continue to engage with our Government of Tanzania counterparts on a wide range of issues, including those related to human rights", read a statement from the State Department adding that it remains committed to values od democracy, rule of law and freedom of expression among others.
Tanzanian authorities have freed two CPJ journalists Muthoki Mumo and Angela Quintal who were arrested yesterday.
Earlier on, Quintal's sister Genevieve Quintal faulted information shared through her Twitter account, saying that it was shared by Tanzanian police.More news: Chinese Workers Made To Drink Urine For Failing To Finish Tasks
Quintal, a former Mail & Guardian editor, and Mumo were detained on Wednesday night by officers reportedly working with the Tanzanian immigration authority.
In a media statement released by the Dirco, the high commissioner of South Africa in Tanzania, Thami Mseleku, informed Minister Lindiwe Sisulu that the passports of Quintal and Mumo had been returned.
Reporters Without Borders, a pressure group, ranked Tanzania 93rd out of 180 countries worldwide in its 2018 World Press Freedom Index, down 10 places from the previous year.
Mabaya said she was unable to locate it and her Twitter and Facebook profiles remain deactivated.More news: New Porsche 911 Passed Final Global Stress Tests Before Arrival
"SOS we are being taken away for interrogation in Dar".
CPJ's executive director Joel Simon has called for their immediate release.
Mabaya said their release came "after a lot of calls" but neither of the women had been given back their passport.
This is a developing story and will be updated as more details emerge.More news: Pakistan vs New Zealand - Highlights & Stats