Two people died, and two others were hospitalised after a room filled with generator fumes in Karachi's Bhittai Colony, 24HD TV reported on Tuesday.
According to police, the incident occurred in a residential quarter where a generator had been switched on during a power outage.
The generator's exhaust smoke reportedly accumulated inside the room, leaving four people affected.
The two critically injured victims later died while receiving treatment at a hospital.
Police said the remaining two victims are still under treatment, while an investigation has been launched to determine the exact circumstances of the incident.
Initial findings suggested the deaths were caused by suffocation after the room filled with generator fumes.