Updated

Just after the tap dance that kicks off the second act, the 323rd performance of Russia's hit musical Nord-Ost took a tragic turn.

Masked gunmen burst on stage and into the audience, firing automatic rifles into the air and taking about 800 people hostage last Wednesday. For those inside, the next 58 hours were filled with fear and hunger, as their captors -- men and women demanding an end to the war in Chechnya -- repeatedly warned the building was mined and they had come to die.

Government officials sequestered themselves in a nearby building, calling in lawmakers, celebrities and journalists to negotiate with the hostage-takers.

Two days after special forces troops released an incapacitating gas into the auditorium and stormed the building, details began to emerge Monday of the events that left 118 civilians dead. However, hundreds of survivors remain in tightly guarded hospitals and the government has refused to identify the gas responsible for all but two hostage deaths.

Actor Mark Podlesny, 22, who played a tap-dancing pilot, was about to say his line when a masked gunman in camouflage jumped on stage.

The gunman fired in the air, as more hostage-takers, including women dressed head-to-toe in black, appeared. They ordered the actors into the front row.

"They said, 'Everyone put your hands behind your head,' and those who didn't were beaten on the head with rifle butts," recalled Yelena Zinovyeva, 18, who was in the audience.

The gunmen told everyone to throw their cell phones and bags into the aisle, then separated the women from the men, she said.

About two hours later, the gunmen handed out the phones, telling people to call their loved ones and "say goodbye," Zinovyeva said.

For food, the captors distributed what remained in the theater's bars -- mostly chocolate. They brought theater costumes and coats from the cloakroom to hostages who complained of the cold.

As the female hostage-takers stood guard and a large explosive device was placed in the center of the orchestra, they told their captives of the war in Chechnya and the relatives they had lost.

Throughout the night, the gunmen freed groups of children and a few women. A 26-year-old woman who inexplicably entered the theater was shot and killed.

Around midday Thursday, lawmaker and singer Iosif Kobzon entered for the first face-to-face negotiations and secured the release of five hostages. The meeting was the start of intensive mediation efforts.

Meanwhile, hostage-takers allowed people to go to the bathroom in small groups, a gunman posted outside the bathroom door. Zinovyeva and her friend Svetlana Kononova saw an opportunity to escape.

They decided to go for it Thursday evening when they saw the female hostage-takers grow agitated, fingering detonators on explosives strapped to their waists.

The two young women jumped from the third-floor bathroom window onto an overhang and then to the ground. Kononova broke both her feet and an officer was wounded shielding the two from gunfire.

From then on, hostages were forced to use the orchestra pit as a toilet.

In calls to loved ones, hostages begged authorities not to end the standoff violently and asked relatives to hold rallies demanding peace in Chechnya. Scattered protests were held Friday around the theater and on Red Square.

One of the last mediators to enter the building was former Prime Minister Yevgeny Primakov. After he brought the hostage-takers' demands to President Vladimir Putin, the Russian leader appointed Viktor Kazantsev to represent the government in talks.

At about 7 p.m. Friday, the hostage-takers warned that if Putin's representative did not call by 10 p.m., they would begin executing hostages, the actor Podlesny recalled.

Kazantsev called Movsar Barayev, the gunmen's leader, and agreed to meet him the next day. He asked Barayev that there be "no excesses" -- meaning killings -- overnight. In a tape of the conversation aired later on ORT television, Barayev agreed.

At about midnight, a man carrying a yellow bag came into the theater, Podlesny recalled. The gunmen began questioning him, believing he was an agent of the security services. The man said his son was a hostage, but when nobody responded to the name he was taken out and two shots were heard. He was the second hostage to die.

Soon after, a hostage charged at one of the captors with a bottle, Podlesny said. A female hostage-taker shot at him and missed, instead hitting a woman in the abdomen and a man in the eye. The two were taken away by medical personnel at 2:45 a.m., and both reportedly survived.

Federal Security Service spokesman Sergei Ignatchenko said a rescue operation was launched after the rebels began executing captives. However, hostages later said no mass executions had begun.

In preparation for the rescue, officers had sneaked into the ground floor to access its ventilation system and set up cameras to monitor the terrorists' movements, according to media accounts.

Before they moved in, special forces began pumping an incapacitating gas into the theater. Two panicked hostages called Echo of Moscow radio when they felt the effects.

"I don't know what this gas is, but I see the reaction," Anna Andriyanova said on the air at 5:30 a.m. "You guys, I'm begging you, I don't know, we can see it, we can feel it, we are breathing into cloths."

Many hostages and captors passed out. Others may have simply been disoriented, said Lev Fyodorov, a former Soviet chemical weapons scientist.

In government-released footage, mostly women hostage-takers appeared to be in the hall when the gas attack began but likely needed Barayev's authorization to detonate explosives. Barayev and his top lieutenants were outside the hall where the concentration of gas was much lower, but still offered little resistance.

At around 5:15 a.m. Saturday, about 200 officers from special anti-terrorist units rushed into the building from several directions, clearing the way with stun grenades.

Barayev and his men reportedly fired several shots before they were killed.

"We encountered automatic gunfire and grenades," said one unidentified commando who appeared on the Russian television, his face hidden.

One female Chechen in the auditorium fired her pistol at the commandos but was killed before she had time to throw a grenade, the officer said. The commandos then finished off some of the Chechens with shots to their heads.

Some Russian media reported the commandos had been given injections to make them immune to the gas.

Afterward, rescue workers streamed into the building to evacuate hostages -- finding a hall full of immobile bodies.

"Inside there was sweltering heat and the nauseating smell of human excrement" from the orchestra pit, said Vadim Mikhailov, who participated in the rescue.

It took about two hours to take out the unconscious hostages.

Once put on the wet pavement, victims were given injections to help overcome the effects of the gas, said Russian lawmaker Valery Draganov.

But rescue workers said they were treating the victims with conventional medicine against shock, not an antidote to the gas. Officials have kept the name of the gas secret.

Fyodorov and others have said a quicker evacuation and more efficient treatment would have lowered the death toll.

By the time over 100 ambulances and ordinary buses brought the hostages to Moscow hospitals, many were dead. Officials initially reported 30 dead among the hostages; later, the death toll reached 118 -- 116 from gas.