Many passengers said they had little option but to take them.
But the other passengers said they did not remember seeing the boy, who had gone on the ride alone.
Four minutes later - not bad, some passengers said - another pulled in.
"I was in the front," said a passenger on the train who did not give his name.
Staff and passengers say that planes are far from full.
"I hope that will be enough," said the young passenger.
Some passengers said they did not mind waiting in lines for security's sake.
Some passengers have said that at least one person died waiting for help to arrive.
Passengers said he told them that his wife and children were aboard.
But as one passenger said: 'Perhaps it's for the best.