Only movement related to health services, pharmacies, police stations, courts, correctional services, fire and emergency services, electricity, water and other utility services will be allowed.
Essential services like medicine shops and health establishments remained open as these were kept out of the purview of the complete shutdown. Petrol pumps are also allowed to remain open on the lockdown days.
Source: https://indianexpress.com/photos/india-news/deserted-roads-quiet-flyovers-mark-this-weeks-first-day-of-lockdown-in-kolkata-6529738/