The State Department confirmed that an American was taken hostage with the three Romanians, but the department gave no further information and it was unclear if the American was the fourth person in the video aired by Al-Jazeera.
Private Romanian television station Realitatea TV reported that an Iraqi-American who worked as the journalists' translator was the fourth person kidnapped.
The video showed three men and a woman seated on a floor, with blankets hung behind them. Two armed men -- their faces covered with scarves -- pointed guns at them.
Media officials in Romania said three of the victims were Marie Jeanne Ion, 32; cameraman Sorin Dumitru Miscoci, 30, from Bucharest-based television station Prima TV; and Romania Libera reporter Ovidiu Ohanesian, 37.
The Romanian government has said the three journalists were abducted Monday near their Baghdad hotel after interviewing Iraqi interim Prime Minister Ayad Allawi. One victim used a cell phone to report the kidnapping.
In the past, kidnappers have demanded that foreign troops leave Iraq in return for freeing their victims. Romania has 800 troops in Iraq as part of the U.S.-led coalition forces.
Romanian Prime Minister Calin Popescu Tariceanu said there has not been such a request.
"At least for now, the disappearance of the Romanian citizens is not related to any concrete demand," he said.
More than 200 foreigners have been kidnapped in Iraq and more than 30 have been killed.
By: (AP) Romanian media officials confirmed Thursday that a televised video showed three Romanian journalists kidnapped in Iraq and a fourth unidentified person, apparently an American.