MOSCOW -- Chechen rebels holding hundreds of hostages at a Moscow theater have agreed to release all 75 foreigners they are holding captive, a security official said early today.

Embassies were being requested to send representatives to the scene to meet their freed citizens, Federal Security Service spokesman Sergei Ignatchenko said. The hostages include Americans, Britons, Dutch, Australians, Austrians and Germans. Hundreds of Russian hostages were not to be freed.

There were no immediate details on how the releases would proceed. The releases were to happen at 9 a.m. local time, Interfax news agency reported.

Earlier today, seven Russian men and women were released, but Ignatchenko declined to specify the reason why they had been chosen. Officials had expressed hopes that the some 30 children also among the captives would be freed today as well.

The band of as many as 50 heavily armed captors seized the theater Wednesday evening during a musical performance, and are demaning Russian troops withdraw from the breakaway Chechnya province.

Earlier Thursday, medics dragged the body of a young woman shot by the rebels from the theater, as the attackers threatened to kill their hundreds of hostages unless the Russian army pulled out of Chechnya. Two women jumped from a window under fire from a grenade launcher and escaped.

Three male captors appeared on Russia's NTV network early today, wearing camouflage and carrying assault rifles. The one unmasked man was identified by NTV as the ringleader, Movsar Barayev, nephew of rebel warlord Arbi Barayev who reportedly died last year.

The network, whose crew was allowed to accompany a doctor inside the theater, also showed two female hostage-takers wearing head-to-toe robes that revealed only their eyes. Arabic script was printed on their hoods, they cradled pistols on their chests and wore what appeared to be explosives taped to their waists and wired to a small button they carried in their hands. No hostages were seen.

The hostage killed by a gunshot to the chest, a woman about 20 years old, was the only known fatality of the crisis as it moved into its second night.

President Vladimir Putin declared that the raid was planned by terrorists based outside Russia. The Qatar-based satellite TV channel Al-Jazeera broadcast statements, believed to have been recorded Wednesday, by some of the estimated 50 hostage-takers who stormed the theater in a rundown Moscow neighborhood Wednesday night just before the second act of a musical.

"I swear by God we are more keen on dying than you are keen on living," a black-clad male said in the broadcast. "Each one of us is willing to sacrifice himself for the sake of God and the independence of Chechnya."

Dr. Leonid Roshal, head of the Medical Center for Catastrophes who was with the NTV crew, said the hostages were trying maintain a calm face and that only two or three were hysterical. He said he had treated the hostages for various minor ailments -- including eye trouble, coughing and hypertension -- and left behind some medication before emerging from the theater without any hostages.

"In general, the situation is calm," he told NTV.

Blow to Putin

The hostage-taking occurred less than three miles from the Kremlin and was a bitter blow for Putin, who repeatedly has said the country has the situation under control in Chechnya, a mainly Muslim republic.

In televised remarks, Putin described the hostage-taking as one of the largest terror attacks in history and claimed it had been planned "in one of the foreign terrorist centers" which "made a plan and found the perpetrators." He didn't provide evidence that the raid was organized abroad.

The U.N. Security Council strongly condemned the raid, calling it a "heinous act" of international terrorism and a threat to peace and security. In a resolution adopted unanimously, the council demanded the "immediate and unconditional release of all hostages."

Russian officials had held out hope for a bloodless resolution until the woman's body was wheeled out on a gurney.

Late Thursday night, liberal Russian lawmaker Grigory Yavlinsky entered the theater for negotiations and came out after an hour, but there was no immediate word on any results.