Reporters from Ukraine, Georgia, Azerbaijan, Latvia and Russia were among those staging brief "lightning actions" outside the Azeri and Georgian embassies.
Two weeks ago Azeri journalist Afgan Mukhtarli, exiled in Georgia, suddenly disappeared. Hours later he was discovered to be back in his homeland, apparently after being kidnapped by the national security services - with or without the collusion of Georgian officials.
Ukrainian TV journalist Angelina Karjakina said: "He's a serious journalist, he was engaged in real investigations, and obviously this was seen as a threat by the Azerbaijani government and leadership."
Latvian investigative reporter Inga Springe was also among protesters and told LSM she was disappointed by the lack of response from Latvian officials, and a lack of criticism over Azerbaijan's bad human rights record despite recent high-level contacts between Riga and Baku, which focused almost exclusively on economic collaboration.
"This is not the first time the government of Azerbaijan has shown its hostility towards investigative journalists. Let's remember Khadija Ismayilova, who spent several years in the prison based on false charges.
"This is an even more outrageous case, because Afgan Mukhtarli was abducted from Georgia, where he lived with his family for two years reporting back home about the Aliev's family abuse of power and corruption schemes. As a part of a European Community and it's crucial values of freedom of speech, I believe that Latvian government can't just close its eyes and pretend that nothing is happening," said Springe.
Similar actions in support of the incarcerated reporter, who faces the possibility of torture by Azerbaijan's brutal regime, have been held around the world.