The hostages - children, parents and teachers - were herded into the school's gym, and held at gunpoint under appalling conditions: in a stifling hot gymnasium, deprived of food, water, and bathroom access, and with bombs hung above their heads. Russian investigators believe 32 terrorists were in the school, including two women who wore belts loaded with explosives.

Sergei Urmanov (left, pictured with his mother), was waiting outside the school with his camera when terrorists stormed the school. "They pushed me inside the school," he says. "I was trying to help children escape by breaking windows and pushing them outside." His daughter, Zalina, his wife, his sister and his two nieces were killed in the attack.

"48 Hours" obtained exclusive footage taken by the terrorists themselves on the second day of the crisis. Pictured is the terrorists' leader, Ruslan "The Colonel" Khuchbarov.

Authorities say the primary demand of the terrorists was to stop the war in Chechnya.

They wanted Russian President Vladimir Putin to withdraw all troops from this neighboring republic that has been at war for independence from Russia.

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The terrorists released babies and their mothers to hostage negotiator Ruslan Aushev (right). At the last moment, exclusive video obtained by "48 Hours" shows a terrorist handing another baby to Aushev.

The boy's mother couldn't leave her older child behind. "I have four children," says Aushev. "I imagined if my children were among the hostages, everything should have been done to save these children."

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Eleven mothers carried out 14 babies. Exclusive video obtained by "48 Hours" shows the mothers, including Zalina Zandrovna (left), painfully walking out the door, each of them leaving an older child behind. One child could be heard crying out, "I want to go with mama."

Zalina Zandrovna was in the gym with her two children, Alana, 6, and Alan, 2, (pictured). She was forced to choose which child to take with her out to safety. She left with her son, Alan, but says she saw fear in her daughter's eyes. "To leave a child behind, it's beyond words," says Zalina. "One has to live through this."

The end of this horrific standoff began with an explosion in the afternoon, 52 hours into the siege. "After the explosion, there was a pile of dead children's bodies, and then complete silence," says teacher Elena Kosumova, who was in charge of the opening day ceremonies at the school. She and her son, Timor, were held hostage during the siege.

Freelance photojournalist Dimitri Beliakov was just 50 yards away from the school, positioned on the fourth floor of a building with members of the Russian Special Forces. "There was just a chorus of screams," he says. "I could see lots of dead bodies."

Moments after the two explosions rocked the building, an enormous gun battle erupted. Special Forces snipers started picking off the terrorists. "They just opened fire," says Beliakov. "They started firing at school." It took nearly 10 hours before all the shooting stopped.

During the shooting, Beliakov photographed a young girl who had been blown out of the gym. Disoriented, she first crawled, and then climbed back inside the building. "She should just run away," says Beliakov. "Instead, she just crawled back. In a few minutes, the roof collapsed."

Teacher Elena Kosumova (pictured) was separated from her son, Timor. "I saw a lot of children climbing over the windowsill. That gave me the idea to escape through the window," she says. "The first people I saw were two men from our town. They were armed. One told me to run over to him. He helped me cross back to safety."

Elena Kosumova's 9-year-old son, Timor (pictured), was later seen sprinting toward freedom in this photo. After the siege, Timor's mother says the third-grader "played on with toy guns, playing war, for one whole month."

Zalina Zandrovna searched for her daughter, Alana (pictured), who she had to leave behind at school. She soon discovered that her daughter was alive: "I entered her ward and saw her lying on the bed. She gave me a smile." Alana, 6, had escaped with some burns, and told her mother that she was saved by the only terrorist who survived.

Larisa Adamovna, Sergei Urmanov's mother, lost all of the females in her family in the siege: her mother, her daughter-in-law and four granddaughters. "There are no girls left in my life," she says. "Female voices are gone. No next generation women."

"48 Hours" helped reunite Dariya Fadeeva, 16, (right) and her sister, Alya, 12, a sixth-grade student. Dariya and her mother were waiting for Alia outside the school during the siege. Alya suffered severe shrapnel wounds to her legs and back, and has been recovering in a Moscow hospital since September. "She doesn't know how many of her friends are dead," says Dariya.

What happened to the little girl who was captured on camera trying to return to the blown-out gym? After a five-day search, photojournalist Dimitri Beliakov found the girl, Aida Sidakova, 7. Aida's grandfather (pictured), who was also a hostage during the siege, looks at photographs of Aida.

At the remains of the school, family members and townspeople have memorialized the suffering by leaving bottles of water and flowers for those who died in the siege.

In this southern Russian town of Beslan, with a population of 30,000, tradition dictates mounting a photograph of the departed on their grave.

Grief is universal at the Beslan cemetery for victims of the September 2004 siege. There were more than 1,200 people taken hostage during the three days of terror. Officials say 330 died, 176 of them children. More than 500 were wounded, and 24 children are now orphans.