Kenyan rescue workers freed a woman from the rubble of a building in Nairobi on Thursday, six days after its collapse.

Then, just hours later, the Kenya Red Cross said three more people — a man and two women — were rescued alive.

NPR's Gregory Warner in Nairobi tells our Newscast unit that the collapse of the six-story building on Friday killed at least 36 people. He adds that dozens are still missing. Here's more from Gregory on the first rescue Thursday:

"Rescue workers were shocked to hear the woman's cries six days after the building had collapsed. They managed to feed the woman an oxygen mask and IV drip, then spent hours with drills to finally free her from under the concrete...."The building collapsed in the heavy rain in a poor neighborhood on the city's outskirts."City authorities say they had earmarked the building for demolition because it was seen as near collapse. But people continued to live there and pay rent. The owners of the building were released on bail but will be charged with manslaughter."

Reuters reports that according to Kenya's Interior Ministry, the residential building that collapsed had been "earmarked for demolition, but local authorities had not acted on the order."

The Associated Press reports that the woman is named Elizabeth Night Odhiambo and her husband says she is eight months pregnant.

"I cannot say the happiness I have," her husband, Stephen Onyango says, per the AP. "I have never had such happiness like this in my life."

A military spokesman tells the wire service that she was found with the help of "trained dogs" and "special equipment to detect breathing and movement."

According to the Daily Nation, a local disaster management authority says the woman "was weak and had no visible injuries." She was transferred to hospital from the scene.

No information was immediately available about the three other people rescued Thursday.

On Tuesday, an infant was found "alive in a washbasin in the debris," according to the AP.

As the BBC reports, "the UN usually decides to call off search and rescue attempts between five and seven days after a disaster, once no-one has been saved for a day or two — but people have been known to survive for much longer."'

That includes Naqsha Bibi, who was found alive in the rubble of her house in 2005 more than two months after an earthquake hit Pakistan-controlled Kashmir. The BBC reports that she likely survived on rotten food and a "trickle of water" inside her collapsed kitchen.

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