The longer video that emerged today shows the three minutes and 52 seconds after the train pulled into Broadway Lafayette station on Monday at 2.30pm.
The footage begins with Penny already with Neely in the chokehold. For two minutes and five seconds, Neely struggled on the floor, flailing his feet.
He went limp after two minutes and six seconds, by which point a by-passer had stepped onto the train.
The man - who can be heard but is not seen - warned Penny that Neely had defecated, which he feared was a sign that he was dying.
'He's defecated on himself... you're going to kill him now,' he said."
"Another man who was helping Penny restrain Neely replied that it was an old stain on Neely's trousers, and that Penny was no longer 'squeezing'.
'He's not squeezing? All right. Because after he's defecated himself that's it. You've got to let him go,' he replied.
He then warned of a 'murder charge'.
The second man turned to Neely and said: 'Hey can you hear me?'. Met with silence, the man told Penny to stand up.
Penny does not speak, but releases Neely and springs to his feet.
The unidentified by-stander can be heard saying: 'That was one hell of a chokehold, man.'
Over the next several seconds, Penny and the other man who had been helping him attempt to put Neely in the recovery position.
After three minutes and 50 seconds, Neely appears to convulse or take a deep breath.
The video cuts out at three minutes and 52 seconds. It is unclear whether he moved again.
