New Delhi, Dec. 1 -- The Delhi Metro Rail Corporation (DMRC) has achieved a significant engineering milestone by successfully constructing an underground tunnel beneath the operational Red Line at Pulbangash, without halting train services even for a single day.

The tunnel is part of the Janakpuri West-RK Ashram Marg extension of the Magenta Line under the Phase IV expansion.

In an update shared on X, DMRC wrote, "This tunnelling work between the Pulbangash and Sadar Bazar stations was especially challenging, as trains on the busy Red Line above were not halted for even a single day, even as the Tunnel Boring Machine (TBM) carefully constructed the tunnel below the elevated viaduct on which trains were operational. Moreover, the Red Lin...