Father and daughter huddled fearfully for three hours until plainclothes police came to their rescue.
"It's hard to describe the relief I felt when I saw the doors to the storeroom open, and several incredibly brave plainclothes police, weapons drawn, motioned for us to leave as quickly as possible," said Nick Handler, of the Philadelphia suburb of Merion, Pa.
"Perhaps it was not rational, but I instantly trusted these guys with our lives. I felt a surge of hope that we were going to be fine."
The 31-year-old Handler, who works on agricultural issues in western Kenya, said the officers rushed into the attack zone "knowing that they were up against heavily armed gunmen and were putting their own lives on the line".
Video from inside the mall shows how security personnel worked to save lives. In one, a man thought to be a plainclothes police officer was seen scooting on his belly across the shopping centre's ground floor to coax a mother and her two children lying next to a cafe counter to stand up and rush out.
The regular mall security guards were unarmed and powerless to stop attackers armed with semi-automatic weapons.
The al-Shabab gunmen appeared to specifically target the unarmed guards as they began their attack, said Ben Mulwa, a community organiser who was shot in the leg near one of the mall entrances. One of the guards was shot through the head just feet from where Mulwa was hiding.
He said the first responders - particularly the lightly armed officers who were among the first on the scene - displayed immense courage in a chaotic and uncertain situation.
"They're only holding pistols. ... The other guys are walking with machine guns," he said. "They could have easily shot them. I found that extremely brave."
Individual acts of courage aside, however, Mulwa and other Kenyans questioned how prepared the country is to confront a large-scale attack. Kenya has been hit by terrorists in the past, and Western officials have warned that malls and other public spaces could be targeted.
"The fact that kind of gunfire can go on in a prime location like that ... I think the response probably wasn't as good as it could be," Mulwa said. "There's some lapses that need to be addressed."
Kenyan army troops took the lead in securing the mall following the initial chaos of Saturday's attack, and it wasn't until late Tuesday that President Uhuru Kenyatta declared the terrorists had been defeated. Mopping-up operations continued into Wednesday, and occasional gunfire could still be heard from the mall.
The official civilian death toll stood at 61 late Tuesday, but officials said more bodies could still be inside the mall, and 71 people remain missing, according to the Red Cross. Six Kenyan security forces, as well as five al-Shabab militants, also were killed.
Among the six Kenyan troops killed, three were first-responder police officers accidentally gunned down by Kenyan army officers in the chaos after the attack, police officials said.
Kenyan officials have been eager to declare the situation under control for days. But the challenge they face could be read on the faces of the soldiers tasked with clearing the mall in the aftermath of the attack. Trudging from the gutted complex to the Oshwal Center, a nearby Indian community centre that had been turned into a makeshift command centre and triage location, the troops looked like they were returning from battle.
Some put on a brave face, like the soldier hauling an anti-tank rocket launcher who wore aviator sunglasses as he ate his lunch inside. But many others looked clearly shaken and worn out.
Ashok Halai, the Nairobi commissioner for St. John Ambulance, which has been providing volunteer emergency medical services since the attack began, said his crews have been coordinating with Kenyan security forces in treating casualties. The operation to clear the sprawling complex has taken a toll on the mood of the Kenyan forces charged with securing it, he said.
"Obviously they are stressed," he said Tuesday. "They would like to have peace. We would like to see this ending."
He said he wasn't surprised that it took so long to bring the operation to a close.
"They've tried their best," he said of the security forces. "Hostages were there. ... Because of the hostages, they might have taken this long."
Two soldiers involved in the operation described the challenges of securing the mall this week even as senior officials were declaring it all but over.
The first floor was soaked with water from overhead sprinklers that went off after fire broke out Monday, and there was no power on the third and fourth floors, they said. That meant troops had to carry out door-to-door searches and hunt for what authorities feared were booby-trapped rooms in near darkness.
"It's really not easy. You don't know where you are and where the terrorists might be," said one of the soldiers. They spoke on condition of anonymity because they were under orders not to speak to the media.
Solomon Ichahuria, a 24-year-old sales clerk who works at a clothing shop on the ground floor, barricaded himself and more than 20 others inside the store when the shooting began.
He said no one found them for about three hours, when an armed man in jeans and a checked shirt - apparently an undercover police officer - knocked on the door. Those hiding inside didn't answer because they were unsure if he was friend or foe. He returned two hours later with a soldier who guided them out, he said.
Ichahuria said the first responders were heroes who "should be celebrated because they did save a lot of lives".
He felt lucky to get out alive after only five hours, though he acknowledged the response could have been better.
"If I was in a G-20 country and it took five hours, in my opinion that would have been a job terribly done. But then now, this is Kenya, and disaster management is not one of our strengths."
- AP