- Angela Quintal, Africa programme, and Muthoki Mumo, CPJ's sub-Saharan Africa representative, were on a reporting mission in the country.
- CPJ says officials searched the pair's belongings and would not return their passports when asked.
The Twitter accounts of two staff of Committee to Protect Journalists (CPJ) who were detained by Tanzanian authorities have been suspended, leading to confusion whether the former Nation reporter Muthoki Mumo and former Mail & Guardian editor Angela Quintal have been released.
A South African news site, News24, reported that a tweet had been sent from Ms Quintal's account before it was suspended appearing to allay fears by confirming that she and Ms Mumo had been released but her family claimed that someone else may have been in possession of her phone.
When Nation tried to reach Ms Quintal on one of her WhatsApp lines, a reply was sent saying: "You've got the wrong number does not anger."
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 @muthokimumosince they were detained and believe both are still in the custody of Tanzanian authorities," Mr Simon wrote on his Twitter account.
CPJ has called on Tanzanian authorities to immediately release the two journalists who were seized Wednesday in Dar es Salaam and taken for interrogation to an unknown location.
Ms Quintal is the CPJ's Africa programme coordinator while Ms Mumo is the sub-Saharan Africa representative. They were detained while on a reporting mission in the country.
Ms Quintal tweeted that officers who identified themselves as working with the Tanzanian immigration authority detained Quintal and Mumo in their hotel room in Dar es Salaam, Tanzania.
CPJ says officials searched the pair's belongings and would not return their passports when asked.
Ms Quintal and Ms Mumo were then escorted from the hotel and taken to an unknown location.
"We are concerned for the safety of our colleagues Angela Quintal and Muthoki Mumo, who were detained while legally visiting Tanzania," said Mr Joel Simon, CPJ's executive director.
"We call on the authorities to immediately release them and return their passports."