One girl, named Nina, said that she came to the Bataclan with her friends and that she was in the hall when they heard some bangs.
"At first we guessed it was part of the show, such as firecrackers. But after we saw lifeless bodies all around, we immediately fell to the floor and the terrorists ordered us to stay so," she said.
She added that she was shocked by what she saw during the terrorist attack.
#emergency units running to scene of #Bataclan theater in #Paris to take care of injured #ParisAttacks pic.twitter.com/HzoJrzvGMz— Caroline Connan (@CarolineConnan) 13 ноября 2015
"They discharged their guns, firing in all directions. The corpses were everywhere. It was horrible, really horrible. It is a good thing that all my friends are safe and sound, "Nina said.
She complained that they waited for police for quite a long time.
From inside #Bataclan theater, eyewitnesses hearing "screams and gunfire" #ParisAttacks pic.twitter.com/UWr8PGnGnG— Jim Sciutto (@jimsciutto) 13 ноября 2015
"We awaited police for at least an hour and a half. All this time we lay on the floor next to the dead, some dying in agony, others crying," Nina said.
Another witness was quoted by media reports as saying that he heard the assailants screaming "Allahu Akbar" while shooting inside the crowd.
The Guardian cited one eyewitness, 57-year-old Marc Coupris, as describing the situation in the theater during the attack as a "battlefield".
"It looked like a battlefield, there was blood everywhere, there were bodies everywhere. I was at the far side of the hall when shooting began. There seemed to be at least two gunmen. They shot from the balcony," he said.
#ParisUnderAttack rue bichat paris10 pic.twitter.com/q69ShHX0ww— petemystrong (@pierre75010) 13 ноября 2015
49-year-old Frédéric Nowak also thought that the shooting was part of the show, according to the Guardian.
"The gig had been going for around 30 minutes. I heard the shots but I thought it was a noise that was linked to the show," he said.
In the long run, it all proved to be a wishful thinking.
"I saw two people with the Kalashnikovs [assault rifles]. One I saw from behind, the other I saw from the front and he wasn't wearing a mask. They were just stood firing at random into the crowd," Nowak said.
"It lasted between 10 and 15 minutes. It was extremely violent and there was panic. The attackers had enough time to reload at least three times. They were very young," he said.
The Bataclan concert hall siege left at least 100 people dead and dozens more injured.
The massacre became the bloodiest of the six simultaneous attacks that struck Paris on Friday night. According to officials, at least 127 people were killed and 180 more injured in a series of explosions and shootings in the French capital.