Shocking moment couple 'smoke crack' on Chicago subway

This is the shocking moment an older couple are spotted apparently smoking crack on the Chicago subway.
The video, shared on LiveLeak on Sunday, shows a woman apparently lighting up a crack pipe for a man in a purple blanket, with plumes of smoke drifting up towards the ceiling.
Others on the train complain about the scene - resulting in a bizarre response from the woman, and then a verbal confrontation.
The video starts off in the middle of the action, as the male half of the couple puffs on something that appears to be a crack pipe.
'On my way to work...' says the man filming the incident.
The sound is muffled, but it quickly becomes clear that another woman has complained to the couple about the smoke.
'He's smoking weed!' says the older woman, pointing off-camera, as if to excuse their own little get-together.
She then confronts the woman, and the pair start a heated argument in which the older woman repeatedly tries to defend herself by pointing out the marijuana-smoker.
At one point she holds a lighter and a hairbrush behind her back. The purpose of the hairbrush in this situation is unclear.
The man recording the event, meanwhile, is left in disbelief: 'Smoking crack on the train!' he says in amazement.'She's tripping!'
It's unclear when the video was recorded.