By Thursday night, barring minor glitches, Central Railway claimed to have normalised up to 85 percent of its suburban operations. By Friday evening, services would be normalised up to 95 percent.
"As the restoration work is nearing completion, we hope that by Friday evening, the situation should return to normal and provide relief to the commuters," a Central Railway official said.
The services on the slow and fast tracks connecting Chhatrapati Shivaji Terminus (CST) with the suburbs and distant towns in adjoining Thane and Raigad districts slowly got back to normalcy.
Train services, both suburban and long-distance, had been disrupted since early Wednesday after a fire gutted the main signal cabin at Kurla station.
The disruptions led to disarray in the services on the harbor line and Western Railway, all of which comprise the lifeline of Mumbai, ferrying over eight million commuters daily.
The resultant delays, cancellations and overcrowding of suburban trains resulted in three commuters getting killed and another 17 getting injured Thursday.
The government and union railway ministry faced flak from the people and the opposition parties for "lack of concern".
BEST and MSRTC (Maharashtra State Road Transport Corporation) will continue to run additional services Friday to clear the rush of commuters.