MUMBAI: Central Railway’s Mumbai Division will operate a megablock on its Harbour Line between Chhatrapati Shivaji Maharaj Terminus (CSMT) and Chunabhatti/Bandra sections to carry out various engineering and maintenance works today. There will be no megablock on the Main Line between CSMT and Karjat/Kasara, which will be a relief for several commuters travelling by local trains on Sunday. On the Harbour Line, the block will be in place on the CSMT–Chunabhatti/Bandra down line from 11:40 am to 4:40 pm, and on the Chunabhatti/Bandra–CSMT up line from 11:10 am to 4:10 pm. Special services will run between Panvel and Kurla (Platform No. 8) at a frequency of 20 minutes during the block period. Harbour Line passengers are permitted to travel via the Main Line and Western Railway until 6 pm during the block period, an official said.