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The Islamic call to prayer rang over Sidoarjo's tightly-packed homes, sweltering in the afternoon sun.
It was a typical Monday afternoon in the Indonesian city and the teenage students of the Al Khoziny Islamic Boarding School were gathering to pray.
"During the Qur'an reading before the prayer, I noticed something falling from the ceiling," 14-year-old Mohammad Fathulbari said.
"But I brushed it off, thinking maybe it wasn't concrete, just something else dropping."
More than 160 children were in the two-storey building when the unthinkable began to unfold.
"Suddenly, the ground shook — it felt like an earthquake," Mohammad recalled.
"I looked up, then I just ran toward the front of the mosque where the imam was.
"Kids were crying everywhere, I couldn't see any way out, but some guys smashed through a wall and that's how we all got out."
In the chaos, about 90 children were able to escape as the building began collapsing.
Many were seriously injured as they were hit by falling concrete and other debris as they scrambled to safety.
"My cousin Rizal was in the middle of the mosque. I tried to look for him, but my friend pulled me back, saying I shouldn't go back in," Mohammad said.
"I kept insisting I had to find Rizal, but I was stopped and people dragged me back by the leg.
"I cried while searching, screaming his name, but he never answered."
The tragedy has traumatised many and has sparked widespread calls across the country to better regulate construction, particularly in Indonesia's schools.
Al Khoziny was just one of Indonesia's tens of thousands of pesantren, a type of religious boarding school that often operates without much government oversight.
The death toll from the collapse climbed overnight and now stands at 66, according to Indonesia's National Search and Rescue Agency.
And after a week of painstaking work, Indonesian rescuers wrapped up the search for survivors today.
A fight to save every child
In the immediate aftermath of the collapse, Indonesia's national rescue agency BASARNAS launched an enormous search and rescue operation.
A handful of children were easier to locate and rescue, but a mammoth task lay ahead to try and rescue other survivors in the 72-hour "golden window" — the critical period after a disaster when those trapped are most likely to survive.
BASARNAS officials said the building collapsed like a "pancake".
"In mosques, prayer areas are wide open spaces, so when it collapsed, there was nothing in between," Emi Freezer from BASARNAS said.?
"We couldn't send in big teams. The level of difficulty was very high, and the working space was incredibly narrow, making it tough for rescuers.
"During breaks, we shared experiences, updates and strategies."
From Monday night through to Wednesday evening, rescue crews worked to prop up tiny gaps in the rubble, call out for survivors and provide water through to the incredibly confined spaces.
Rescuers had to use hand tools so as not to disturb the rubble and cause any further collapses.
One rescuer, Nur Hadi Santoso, fed a hose through the rubble to try to give a child drinking water.
"I remember about 24 hours in I heard a boy's scream near me — I thought I had to give him water," he said.
"I created a small opening and ran a drinking hose through. I used a torch and could only see the palm of his hand.
"He took the hose and shared the water with his friends."
Crews worked long hours, delicately and painstakingly making pathways to the surviving children they could hear under the heavy rubble.
"A lot of the children were wedged in tiny voids, barely the size of my own body," Nur Hadi Santoso said.
"We had to crawl in to pull them out, all the while tonnes of rubble sat right above us.
"The risk of a secondary collapse was about 99 per cent, we hung onto that 1 per cent chance it wouldn't give way."
On Wednesday, some 48 hours after the school collapsed on its foundations, five children were methodically saved, prompting enormous relief from rescuers.
"Thank God. The moment I saw the faces of those boys for the first time, all the fatigue just vanished. It was a real surge of energy," Nur Hadi Santoso said.
Emi Freezer said saving even just one life was an "invaluable blessing".
"It's truly a gift for us, nothing compares — it's a reward we'll carry for life."
'We're in such shock'
Since Monday night, a large crowd of parents and family members had been gathered not far from the school, sleeping on cardboard mats and tiled floors, desperately waiting for any news about their loved ones.
But by Thursday morning, no signs of life could be detected under the rubble.
Indonesia's Disaster Mitigation Agency, along with BASARNAS, broke the news to families that they had to move the operation into a recovery mission for the bodies of the teenagers.
On Thursday afternoon, families held prayers, weeping with each other and remembering their sons, nephews and brothers.
"He's such a good boy, he's so handsome," Ayuli, the aunt of missing 16-year-old boy Mohammad Rizki Saputra said.
"Rizki is an obedient child, accepting, he never asks for anything.
"He likes to pray since he started at this boarding school. We're in such shock because he's such a good boy.
"We're not blaming anyone … we're religious people and we believe we each have our own destiny."
Many families also told the ABC they did not blame anyone. They said they had accepted the deaths as part of God's will, and simply wanted the bodies back quickly for burial.
A wake-up call on construction safety
The deaths have sparked widespread calls for construction reform, with many in the industry not surprised that such a collapse was able to happen, especially in an area outside of a major city.
A spokesperson at the Disaster Mitigation Agency described the event as the first time a building had collapsed without any triggers like an earthquake, but that it was an "eye-opener".
"Too often, people either ignore the national standard, or fail to use it as a reference during construction," Structural engineering expert, Mudji Irmawan from the Surabaya Institute of Technology told the ABC.
"There's been a lot of effort to promote and socialise these regulations, but many developers still see compliance as a burden.
"They think the standards make projects harder … some building owners treat construction like it's easy work until something goes wrong.
"Only then do they realise why these codes exist in the first place."
Al Khoziny did not respond to the ABC's questions, including questions about the advice it had on the safety of the construction.
In the wake of the tragedy, Indonesia's Religious Affairs Minister has pledged to pay "special attention" to ensure the construction of pesantren complies with safety standards, to safeguard children.
According to a Reuters report, the country's Public Works minister told local media that only 50 of the country's thousands of pesantren had building permits.
"This incident should serve as a hard lesson for all of us," Mr Irmawan said.
"Personally, I was devastated. I cried when I saw the rubble of that collapsed building. As an engineer, I feel a deep responsibility for the outcomes of construction.
"The key message is this: we can't wait for more casualties before we act."
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