When the gunman began to attack the Al Noor mosque, Ahmed Alayedy scrambled to get to the nearest emergency exit. He was the first one there.
"I tried to open the door," he said. "But it doesn't open."
Alayedy and other survivors of the March 15 mosque attacks in New Zealand have described a scene of confusion and terror at the door on one side of the main prayer room, in the first accounts of the role the door played.
Alayedy said so many people began crushing him against the door that some of his ribs cracked. Another survivor, Khaled Alnobani, says he thinks as many as 17 people may have died trying to get out through the door.
The mosque says an electrician disabled that system the day before the attack, although some of those who escaped question whether that was the case.
What is clear is that nobody managed to open the door that afternoon.
With the gunman in the middle of the room, the door represented the only escape route for those on one side of him, at least until people started smashing windows to escape.
Fifty people were slaughtered by the gunman at two Christchurch mosques during the attack, including 42 who died at Al Noor.
Alayedy and others say that if the door had been wide open like it usually was during Friday prayers, many more people might have escaped.
Shagaf Khan, the president of the Muslim Association of Canterbury which oversees the mosque, said the door was closed and latched much like the front door of a house. He said it wasn't locked, although worshippers may have believed it was in the confusion.
He said an electrician had tested the new electric locking system on Thursday, and then disengaged it for Friday prayers. He said that to open the door, somebody needed to turn a lever. It was just happenstance, and perhaps the cool weather that day, he said, which meant the door wasn't wide open as usual.
"We were prepared for an emergency like a fire or an earthquake, and people would still have time to get out. This is something totally different. You don't put this in your emergency plan."
Alayedy said that in the confusion, he can't be sure if he simply failed to turn the lever properly or if something else stopped the door from opening.
Alnobani, said he, too, tried to open the door and it didn't work, and he's familiar with the lever. He said he believes the door was electronically locked. Simply pushing a button next to the door would have unlocked it, he said, but nobody knew about the new system.
Khan said the mosque was in compliance with regulations, which require emergency exits to be clear from objects, easily accessible, and unlocked.
Police said the scene examination is part of their investigation and they will not be commenting while the investigation is ongoing.
Australian Associated Press