Mumbai, April 6 -- The sound of firecrackers greeted residents near Parel and Prabhadevi stations early in the morning on Sunday as Central Railway and the Maharashtra Rail Infrastructure Development Corporation (MRIDC) authorities and workers celebrated the demolition of the British-era Elphinstone road over bridge (ROB). The ROB had served as a key east-west connector for 115 years. The demolition required an additional 90 minutes beyond the 6.5-hour mega block announced earlier, inconveniencing rail commuters and forcing many to walk along the tracks. While CR and MRIDC refused to comment on the delay, officials involved in the demolition said the process took more time than anticipated as the bridge was very old and girders were rusted. The Western Railway (WR) had removed a portion of the ROB last month. To remove the two remaining girders spanning 37 metres each over rail lines, the CR enforced a mega block for 6.5 hours starting 11.15pm on Saturday. Though the block was supposed to end at 5.45am on Sunday, train movement for all railway lines was cleared only at 7.14am, CR officials said. Divisional Railway Manager (DRM), Mumbai Division, Hiresh Mina, who was responsible for planning and clearing the mega block, did not respond to queries from HT regarding reasons for the delay. MRIDC officials too chose to stay mum on the subject. A senior CR official involved in the demolition said the exercise was delayed due to the age and the 'uncertain residual strength' or load-carrying capacity of the bridge. "We had to approach the dismantling with extreme caution. Gas cutting took extra time as girders were fully rusted, covered in dust and corroded," the CR official said. The presence of high-rise buildings in the vicinity restricted the movement of cranes for lifting the girders while the narrow approach road and limited space on girder flanges posed challenges for gas cutters, the official noted. With the old ROB now demolished, decks are clear for construction of a double decker bridge. The lower deck of this bridge will cater to motorists travelling between Parel and Prabhadevi while the upper deck will be part of the Sewri-Worli elevated corridor connecting the Atal Setu with the Bandra-Worli sealink. This project is likely to be commissioned by 2026-end, officials said....