The union representing media workers in Venezuela said all but one of those detained were employed by foreign news organisations and were released later on Monday, with one reporter deported.
Foreign news media have long faced restrictions in Venezuela, with very few being granted visas to work in the country.
Their detention came as Delcy Rodríguez was sworn in as the interim president and shortly after she said that she was willing to co-operate with the Trump administration, which has said it would "run" Venezuela.
The union said the media workers were detained by Venezuelan security forces at the National Assembly and its environs, and in the neighbourhood of Altamira - all in the capital, Caracas.
At least two of them were seized by agents working for Venezuela's military counterintelligence agency, while others were detained by Venezuela's intelligence service.
They said they had their equipment searched, their phones checked and their social media posts and messages read, the union statement added.
A Colombian and a Spanish reporter were also detained at Venezuela's border with Colombia near Cúcuta.
The two reporters were held for hours incommunicado before being released back into Colombia, the statement said.
The union called the incidents "alarming" and called for the release of 23 media workers who remain in detention in the country.
