Metro commuters had a harrowing time on Thursday as four electronic flap-gates at Chandni Chowk station malfunctioned for the entire day apparently because of a software glitch.
Officials said six of the 12 flap-gates at both ends of the station ' one of the busiest in Metro, recording a daily footfall of 50,000 ' developed snags in the morning. They could not be repaired by the night.
As a result, commuters had to stand in serpentine queues to enter or leave the platforms, triggering chaos on the station premises.
"The gates developed a snag because of a problem in the software that runs the device. We called our engineers and also their counterparts in Centre for Railway Information Systems (Cris), which is in charge of the system," said Protyush Ghosh, deputy general manager (general), Metro.
The software runs the radio frequency identification device in the flap-gates, which reads the validity of a card or coupon before opening the flaps. "The software got corrupted. This is a one-off incident. We will fix the problem tonight," Ghosh said.
A similar lapse at the station in August 2011 had triggered an unrest, with commuters running riot, smashing glasspanes and breaking token-vending machines.
Sougata Paul, who got off at the station in the afternoon, found the tail of the queue at the southern exit gate reaching the platform. "I had to wait for over 10 minutes before I could reach the flap-gates."