But the White House said no prisoner release appeared imminent and a major Sunni Arab clerical group said it could do little to help win Carroll's freedom because it did not know who was holding her.
The kidnappers of 28-year-old Carroll, identified as the previously unknown "Revenge Brigade," have given until Friday evening for all Iraqi female detainees to be freed or they would execute her. However, Iraqi kidnap groups often set such deadlines only to ignore them and continue holding captives.
New images showing Carroll surrounded by three armed and masked gunmen were aired Thursday by the Arab TV station Al-Jazeera. The 20 seconds of silent footage were from a tape of which excerpts were broadcast Tuesday with the 72-hour deadline.
"I, her father and her sister are appealing directly to her captors to release this young woman who has worked so hard to show the sufferings of Iraqis to the world," Mary Beth Carroll told CNN's "American Morning."
A White House official told CBS News that Carroll's plight is dire and underlined that the U.S. never negotiates with terrorists.
But Iraq's deputy justice minister, Busho Ibrahim Ali, said six of the eight Iraqi women in custody are expected to be released next week, but he stressed that any release would "not be part of any swap with any kidnappers."
"I insisted that the Americans should bring (the women's) files and release them and they will be freed next week along with other detainees," Ali told Associated Press Television News. He did not elaborate on who the other detainees were, but said the recommendation to free the women was made Monday.
Speculation that the Iraqi women may soon be freed raised hopes for the release of Carroll, a freelance journalist who was working for the Christian Science Monitor when she was seized Jan. 7 in western Baghdad. Her translator was killed.
But Carroll's mother told CNN that they had discussed the eventuality of being kidnapped, and the Carroll knew the risks.
"I feel also after being in Baghdad for two years that she knew what she was doing," Mary Beth Carroll said. "She knew what the dangers were. She knew what the risks were. And she chose to accept those because what she was doing to communicate to the world the sufferings of the Iaqi people was important."
U.S. military officials repeatedly refused Thursday to confirm whether any release was imminent. In Washington, White House press secretary Scott McClellan said the Bush administration was working hard to secure Carroll's freedom but said no Iraqi detainees were expected to be released soon, citing information from the U.S. Department of Defense.
"Any time you have an American held hostage, wherever they are, they are a priority for the administration," McClellan said Thursday. "And we want to see her safe return. As I indicated yesterday, too, I don't think it's really helpful to go beyond that at this point."