It came when the city was asleep. At 3.02am local time, residents were woken by a tremendous shaking. Eye-witnesses described scenes of apocalyptic terror as people ran barefoot into the streets in blind panic. The city was plunged into darkness as the electricity was cut off. Yesterday the city was without water, and most phone lines were down.
Muzzafer Yarla was seeking some respite from the hot August night on the balcony of his Istanbul flat when it hit. The seven-storey building collapsed beneath him like a house of cards. Mr Yarla was hurled into the street, miraculously surviving. But yesterday his only thoughts were for his family, buried in the rubble of his home.
"Tell me my children are alive," he pleaded to reporters from his stretcher. But moments later rescue workers found the first corpse when they stumbled across bare feet sticking through the rubble. There was a deathly hush as neighbours identified the corpse, then neighbours struck up a wail of grief.
"My Hali, my Hali," screamed one of the women. "Is this the way to go?"
"Until recently we were hearing sounds," said another survivor, Birol Lule. "My friend Saban was calling out: `Help me.' But for a while now there has been no sound." By a grim irony the construction worker found himself among hundreds of Istanbul residents scrabbling to shift the rubble of collapsed buildings by hand.
The Turkish Prime Minister, Bulent Ecevit, was on the verge of tears as he toured the disaster site. "The loss is huge," he said in a broken voice. "It is the biggest natural disaster I have witnessed ... May Allah help our state and our people."
The quake was so immense that the shock was felt in the Turkish capital, Ankara, 275 miles away. A major oil refinery burst into flames near the epicentre, close to the industrial city of Izmit, 55 miles from Istanbul.
It was nearby Golcuk which was hit worst. In this small town 160 Turkish sailors died when two buildings they were living in collapsed.
Hamza Bikbay and his wife, Sema, were dragged alive from the rubble of their home. "Everything started collapsing," said Mr Bikbay. "We held hands and I said, `OK, we're dying'."
A lot of people stared death in the face in Golcuk yesterday. "My friend was pulled out dead from these buildings," said Emre Kapiskay. The 17- year-old tried hard to blink back the tears. "Last night everyone was in a panic. We kept running but the roads were blocked by rubble so we ran back."
Sema Tura's brother and niece are dead. Yesterday, she was waiting for news of her aunt. "I have no injuries," she said. "But I have fear, lots of fear."
Rescue teams dug at the ruins of a naval building in a desperate search for 200 sailors buried in the rubble. Around 250 had been initially lost and 20 had so far been brought out dead. Another 23 were rescued injured.
"We heard a great noise and ran towards the building where our friends were. It was completely destroyed," said a naval guard. "We struggled to dig them out with our bare hands."
The Marmara Sea facilities, one of the command and control centres for the Turkish navy, are located near the epicentre of the quake. Those trapped included both serving and retired officers as well as civil personnel.
At Golcuk, ambulances, sirens blaring, wove through traffic-clogged streets, but reporters saw little sign of rescue teams searching the damaged buildings on the main road to town.
Desperately waving addresses of their collapsed homes, people in the town ran after a handful of motorised cranes, pleading for help.
Throughout Golcuk, people were frantic to save loved ones and friends. Some refused to lose hope, digging with their hands, hour after hour. Others gave up in despair. And many blamed city hall and the military for failing to give them the help they needed.
"My loves, my children are there, my 15-year-old son and my daughter. But no one is fighting to save them," Gulser Onat screamed at the debris of the family apartment.
Sometimes, help did come. And sometimes it wasn't enough. Mahir Eryilmaz dug for 12 straight hours, trying to free his nephew. When a crane finally arrived, its reach wasn't long enough. Nor were the ladders of the fire brigades battling a nearby blaze.
"The crane couldn't do anything. No one is helping us. Neither the city nor the military," Mr Eryilmaz said as he continued bashing the concrete that pinned his 21-year-old nephew's feet.
Mr Ecevit arrived to watch the rescue operation and said: "It is becoming clear that one of the most badly hit areas were the naval forces facilities at Golcuk. Golcuk was right on the fault line. There was a handover ceremony there yesterday and there were a lot of admirals and naval officers. Most of them stayed at Golcuk."
The mayor, Ismail Baris,begged the outside world for assistance. "We fear that there are many more under the rubble," he said. "We desperately need help - from machines to food, everything."
With most of their phone lines dead, the people of Istanbul turned to the Internet to communicate with the outside world. Most told of the unbearable horror and fright they experienced.
"I felt a lot of aftershocks," Ahmet Tunca said in a dispatch shortly after the first shock. "I also felt dead cold, and that made my kidneys work fulltime, all the time. The sound is still ringing in my ears and it is still terrifying me and I hope that we don't get another tremor like that within the foreseeable future."
"The earthquake started off very, very strong knocking everyone out of their beds," wrote Kadir Bahcecik, a central Istanbul resident.
"As I tried to sit up in my bed I heard items falling off the shelves with crashes and a deafening rumbling sound everywhere. Had the full 45 seconds of the quake been that strong I think it would have been one of the worst disasters in the history of mankind."
"The aftershocks were the most demoralising part of the horrible night," Mr Bahcecik continued in an e-mail dispatch to the BBC.
"Living in an eighth-floor flat I felt every single one of them. I lost count of them as a slight tremble was felt more frequently than every five minutes."
"I'm so afraid," said Fatih Gurhan. "My parents are crying now because my young brother was killed in the earthquake."Reuse content