It was 8:40 pm on a Saturday cooled by spring rain and Romain was ordering with his wife and six-year-old son at the counter of the Starbucks cafe on the Avenue de l'Opera in the heart of Paris.
Just then he looked out the window and spotted a man attacking a passer-by on the sidewalk across the street.
"He had blood on his face and a blade in his right hand," Romain, 34, told AFP.
"His victim dropped his kebab and was able to get away. Then the man crossed the street and started coming toward us."
"He approached calmly, a total contrast with the panic all around him. People were screaming and running," Romain said.
"He had a beard, not very long, and was dressed normally. He didn't fit the stereotype" of a jihadist.
"He said "Allahu akbar" ("God is greater") twice, very quietly -- it chilled the blood. We shut and locked the door, so he turned around," he said.
"A taxi stopped, and he stabbed through the window several times, which the driver was able to avoid, then he went on his way" toward the Rue Marsollier and a bustling district of theatres and restaurants, popular with both tourists and locals.
Romain called the emergency services at 8:46 pm, one of the first to alert the police about the attack.
- 'Shoot, shoot!' -
Two minutes later a nearby patrol of three officers was alerted by people fleeing the scene.
Witnesses described a frenzy of fear that quickly spread to nearby streets.
When police caught up with the attacker on the Rue Marsigny, he started walking towards them shouting "Shoot, shoot -- I'm going to stab you!"
It was 8:56 pm when one of the officers tried twice to subdue the man with a Taser, without success.
One of his colleagues then drew his pistol and fired twice, striking the man in the chest. He dropped the knife, its 10-centimetre blade (four inches) broken.
At 9:24 the assailant was officially declared dead, but the surrounding area remained cordoned off for hours with a massive police presence.
Behind the police lines, dozens of people gathered: some were tourists visibly alarmed, others were just getting out of a show at the Bouffes Parisiens theatre.
The attacker was not carrying ID papers, but investigators later named him as Khamzat Azimov, a 20-year-old born in Chechnya who moved to France with his family as a child.
He did not have a criminal record, but was on watchlists for suspected radicalists who could pose a terror threat, and had been questioned by investigators just last year, officials said.
A 29-year-old man was killed during his stabbing spree and four other people were injured, two of them seriously.
Prime Minister Edouard Philippe said police had arrived just five minutes after being alerted, and the attacker was dead "less than nine minutes later".
"The speed of this reaction has obviously avoided a much higher toll," he said.