Kuwait City — Kidnappers of American journalist Jill Carroll have threatened to kill her if their demands are not met by Feb. 26, the owner of a Kuwaiti TV station that has aired a new tape of the hostage said Friday.

Al Rai satellite station owner Jassem Boudai said the kidnappers set "more specific" demands than the release of all Iraqi women from prison, which the group laid down in the first videotape released last month. Boudai refused to elaborate.

He said that "sources close to the kidnappers" told the station Friday of the new deadline.

The small, privately owned station aired a tape Thursday showing Carroll, 28, appealing for her supporters to do whatever it takes to win her release "as quickly as possible."

The U.S. military has released five Iraqi women from detention but said the releases were routine and not part of any swap for Carroll. Five Iraqi women remain in U.S. military custody.

Friday's message was not conveyed in the latest videotape, but by "another method," Boudai said. He did not elaborate, and it was unclear whether he passed the latest demands along to authorities.

Boudai said the sources claimed Carroll, who was abducted in Baghdad on Jan. 7, "is in a safe house owned by one of the kidnappers in downtown Baghdad with a group of women."

He said the sources also claimed Carroll was in good psychological condition and was doing housework with the women in the place of her detention. The sources also said the kidnappers denied killing Carroll's translator when they abducted her at gunpoint, as has previously been reported.

Later Friday, Boudai told CNN that he believed Carroll's kidnappers were the same ones who seized two Italian aid workers in September 2004 and released them several weeks later. Italian media said a $1 million ransom was paid in that case.

"I think they are the same group who contacted us last year when the two Italian girls were kidnapped in Iraq," Boudai said.

The station on Friday also reported the latest threat by the kidnappers to kill Carroll, a freelance reporter for the Christian Science Monitor.

Monitor spokeswoman Ellen Tuttle declined comment on Friday.

Two previous tapes of Carroll were aired without audio by Qatar-based Al-Jazeera on Jan. 17 and Jan. 30. The first tape made by the kidnappers, who identified themselves as the "Revenge Brigades," included a threat to kill Carroll within 72 hours unless all Iraqi women were released from custody.

Security experts said kidnappers' choice of Al Rai for the latest tape indicated an effort to increase pressure on the U.S. government.

Al Rai broadcast the new 22-second video in its entirety and with Carroll's voice, unlike Al-Jazeera, which has a policy not to broadcast voices. She spoke of having sent two letters but did not say to whom.

"I am with the mujahedeen," she said. "I sent you a letter written by my hand, but you wanted more evidence, so we are sending you this letter now to prove I am with the mujahedeen."

An Al-Jazeera employee, who spoke on condition of anonymity because he is not authorized to make statements for the station, confirmed the first two videos referred to a letter. The station did not mention any letters when it aired the videotapes. It did report that the kidnappers were demanding the release of women held prisoner in Iraq.

When the new tape was delivered to Al Rai's Baghdad office, it was accompanied by a letter written by Carroll, the station said.

Boudai said his station gave U.S. authorities the letter, which he described only as "sensitive." The station did not reveal its contents, he said, out of concern for the reporter.

Before the latest threat was reported, State Department spokesman Sean McCormack said the United States continued "to make every effort to secure her release, to see that she's back safe and sound with her family and her co-workers."

Some analysts said Carroll's kidnappers used the relatively unknown station to get more of its message across and to avoid being tainted by Al-Jazeera's reputation as being biased toward insurgents.

Al-Jazeera came under criticism for airing videos showing al-Qaida in Iraq with hostages they soon beheaded. The station cut the tape when masked gunmen drew knives and moved toward their doomed victims.

Since then, Al-Jazeera has sought to air just enough material for news value without appearing to be a conduit for gruesome propaganda.

"There are a lot of question marks for insurgents at Al-Jazeera because they don't air all their tapes in entirety, or not immediately or sometimes not at all," said Mustafa al-Ani, director of terrorism studies at Gulf Research Center in the United Arab Emirates.

"But these small stations will jump at such opportunities because they aren't famous," he said. "Very few people had heard of Al Rai before that tape, but now people all over the United States know it."

A top U.S. media analyst said being able to get the full message out could put public pressure U.S. officials to question the Bush administration's approach to Iraq.

"These videos will prompt us to feel fear, hope, heightened anger or frustration about a matter as viewers will have little control over, and this could lead us to putting more pressure on our public officials," said Bob Steele of the Florida-based Poynter Institute for Media Studies.