Many people thought an earthquake had hit tremor-prone Istanbul when two powerful explosions rocked the city on Thursday morning.
There were scenes of shock and anger
"The immediate reaction was people shouting 'earthquake'. But after a few seconds we realised it was not an earthquake but something else," Rakesh Jobanputra told the BBC.
"People knew it was an attack or a bomb", Mr Jobanputra said, not least because the area is "full of modern buildings, symbols of capitalism".
All the windows in the 15-storey HSBC building - the target of the first attack - were blown out by the explosion, sending shards of glass crashing to the ground.
Pools of blood were visible in the street, which had been packed with shoppers at the time of the blast.
Murat Emre Duman was working in a building near the bank.
"I saw yellow smoke" coming out of the tower, he said, and "shattered glass from cars and windows everywhere".
He called a friend whose 28-year-old wife worked in the building, he said, but soon learned she had been killed in the explosion.
"I saw her body," Mr Duman told BBC News Online. "My friend doesn't even recognise me. He's in a state of shock."
For Ozhan Orge, who was also working nearby, the reaction was "definitely anger towards the terrorist attacks.
"Everybody ran to the windows, shouting 'God damn it, God damn it.' Our friends were working in that building," he said.
Kerem Gunay had just driven past the bank when the explosion took place.
"There was total chaos, a horrible scene," he told BBC News Online. "You just want to get away from it."
Television footage showed the wrecked facade of the HSBC bank, water gushing from a burst mains onto mangled cars and debris littering the street below.
Shocked people, caked in dust, milled around, some shouting, others helping blood-soaked victims to safety.
Mehmet Susakli was working on the eighth floor of a building close to HSBC when the bomb went off.
"I ran to the hospital to give blood but couldn't because of the crowds," he told BBC News Online.
As ambulances raced to the scene, bystanders began digging with their bare hands, trying to reach people apparently trapped under tons of wreckage.
"People are helping however they can," Damla Ozluer told BBC News Online.
"We're surprised and confused. We weren't expecting another explosion so soon," she said, referring to the bombing of two synagogues at the weekend.
Outside the UK consulate - Thursday's second target - confused and wounded people staggered over rubble and twisted metal as smoke and dust blotted out the sunlight.
A plume of thick, black smoke billowed from the consulate grounds, while outside the gates cars lay crushed by mounds of debris flung across the street by the force of the blast.
Eyewitness Fabrizio Mambrini told BBC News Online: "The scene is surreal. Half of the city is empty, no traffic, the other half is packed with traffic, tens of ambulances wailing over the streets.
The UK consulate was badly damaged
"There are people under the concrete, and in the streets people crying everywhere."
Rakesh Jobanputra spoke of a city in chaos.
"Blood and tears [are] everywhere," he told BBC News Online.
"People are shocked, angry and mourning loved ones, like they were five days ago".
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