Tanzanian authorities have freed two Committee to Protect Journalists staff, Ms Muthoki Mumo and Angela Quintal, who they had detained in an unknown location.
South Africa's Department of International Relations and Cooperation (DIRCO) said the two journalists were back in their hotel.
"South Africa's High Commissioner Mr Thami Mseleku is meeting with them to discuss last night’s events. He will then engage Tanzanian authorities. DIRCO spokesperson, Mr Ndivhuwo Mabaya, spoke to Ms Quintal this morning," the SA Foreign ministry said in a tweet on Thursday.
A US State Department spokesperson had on Thursday told the CNN that it was "closely following" on Tanzania’s arrest of the two journalists.
"We continue to engage with our Government of Tanzania counterparts on a wide range of issues, including those related to human rights," the US State Department said.
"The United States remains committed to the values of democracy, rule of law, freedom of expression, and prosperity in Tanzania."
Ms Mumo, a former reporter with Kenya's Nation Media Group, and her CPJ colleague Ms Angela Quintal were detained on Wednesday in their hotel room in Dar es Salaam and then taken to an undisclosed location by people who identified themselves as immigration officials.
Earlier on Thursday, CPJ's executive director Joel Simon said the journalists' mobile phones may have been compromised.
"It's extremely alarming that Angela Quintal's devices may have been compromised. We have had no contact with @angelaquintal and @muthokimumo since they were detained and believe both are still in the custody of Tanzanian authorities," Mr Simon wrote on his Twitter account.
CPJ called on Tanzanian authorities to immediately release the two journalists.
Ms Quintal is the CPJ’s Africa program coordinator while Ms Mumo is the organisation’s sub-Saharan Africa representative.
The two were on a reporting mission missing in the country.