The BBC reporter in Tigray has been released without charge.
Girmay Gebru was taken from a café in the regional capital, Mekelle, on Monday, and detained by the military.
A local journalist, Tamirat Yemane, and two translators – Alula Akalu and Fitsum Berhane, who were working for the Financial Times and the AFP news agency – have also been freed.
No official reason has been given for their detention.
Girmay, who works for BBC Tigrinya, says he is happy to be home after two days in detention.
It is not clear whether four of Girmay’s neighbours detained alongside him on Monday have also been released.
The BBC says it is “pleased and relieved” Girmay has been released.
“We are seeking a full explanation from the authorities as to why he and others were arrested when they had clearly committed no offence,” the BBC said.