KOLKATA : Frequency of special trains between Howrah and Delhi, Mumbai, Ahmedabad will be reduced from daily to weekly on the request of the West Bengal government in view of the prevailing COVID-19 situation, railway officials said on Monday.The frequency of 02303/02304 Howrah-New Delhi-Howrah Special (via Patna) and 02381/02382 Howrah-New Delhi-Howrah Special (via Dhanbad), which were introduced from June 1 as per the schedule of Poorva Express, would now run once a week, an Eastern Railway official said."Both the above pairs of trains will run as per schedule up to July 10 from Howrah and up to July 11 from New Delhi.