The incident, which took place at 11.25 AM, unnerved passengers who were either office-goers or school students and had to wait inside the pitch-dark train till the Metro authorities came to their rescue.
The rake developed a snag soon after leaving the Park Street station heading north towards Dum Dum.
Thousands of commuters were inconvenienced as normal services were disrupted for about two hours.
The passengers were evacuated from the rake with ladders.
"We had to wait for a long time in darkness till we were rescued from the hell hole," one of the traumatised passengers said.
Children and women had fallen unconscious during their ordeal and had to be rushed to hospital .
Denying the charge, the Kolkata Metro authorities and said that the crisis management team was swift to swing into action and evacuate stranded passengers from the tunnel.
"The crisis management team swung quickly into action and all the passengers were brought out safely from the train after evacuating them along the tracks onto the Park Street station platform," CPRO of Metro Railway R N Mahapatra said.
Mahapatra said that power was switched off to de-energise the third rail, from which the train draws power, for evacuating the passengers.
The railway authorities ran truncated services from Dum Dum to Central on one side and Mahanayak Uttamkumar (Tollygunge) to Kavi Subhas (New Garia) on the other side.
Mahapatra said that an inquiry had been ordered.