A graphic designer who hid in a cupboard under a sink while the Kouachi brothers held his boss hostage said his heart "stopped beating" at one point during the ordeal.
Lilian Lepere was working at a print company in Dammartin-en-Goele when Cherif and Said Kouachi laid siege to the building after killing 12 people in Paris.
The 27-year-old broke down in tears while recounting his ordeal to French television station France 2; the first interview he has given since the drama ended.
"One of (the brothers) came and opened a cupboard next to mine," he said. "Inside he found nothing interesting to him. Then he went towards the fridge.
"He asked his accomplice if he wanted to drink something and he responded 'No, and this isn't a time for that'.
"I thought that… if he is looking for something, for food supplies, he will look through all the cupboards.
"So he went towards the fridge and came back towards the place I was hidden in and he drinks (some water) just over my head.
"He was drinking just above me. I could hear water flowing just over my head, because my head is next to the washbasin. I can see his shadow through the opening between doors.
"I moved a little bit. My back was stuck against the pipe which was leaking. I felt water flowing; a surreal moment, completely surreal, and I said to myself 'it's like in a film. We only see that in films'.
"The brain stops thinking, heart stops beating, breath is stopped and you wait, because that is the only thing you can do."
The print firm's boss Michel Catalano told Mr Lepere to hide in the back of the building when he saw the gunmen arriving, allowing him to feed vital information to the police.
Despite hardly being able to move in the confined space, Mr Lepere described the moment he reached for his mobile phone and texted his mother who contacted police.
"It's not big. Imagine something like 70 cm by 90 cm and approximately 50 cm deep. If you move on one side you might open the door and on the other you hit the wall. So you don't move.
"At some point I told myself I should go for it, even if it makes a noise. Phones were ringing here and there in the company, so those noisy moments allowed me to move.
"I was saying that to myself to give me some hope. And after some time, after fifteen minutes, I was able to reach my mobile phone.
"At that point I knew I was in contact with the outside world and it was really good for morale. From that point everything was done between my phone and my mother's phone."
Mr Lepere's mother passed her phone to police who communicated with her son for the duration of the siege.
It was through this series of text messages that police were able to coordinate their plan to begin the assault on the Kouachi brothers.
"(The police) were using only one phone to communicate (with me) and I was able to give them as much information as I could using my ears and feelings," he said.
After eight hours, as night drew in, police launched their attack killing both brothers and ending three days of terror.
