KOLKATA: A day after objecting to "gradual dilution" of lockdown in West Bengal , the Union home ministry again wrote to the state government on Sunday asking it to take necessary action to ensure strict adherence to the curbs following alleged violation incidents in Murshidabad and Siliguri.The letter written by a deputy secretary in the MHA (internal security division) to the state chief secretary and the director general of police (DGP) was sent on Sunday, officials said."It has been reported that there was a large assembly of people in establishment dispensing essential commodities and shops dealing with non-essential commodities were open in Siliguri. Further, the lockdown was also violated in some mosques in Murshidabad district," the letter stated."It is requested to take necessary action in order to ensure strict adherence to lockdown measures. District authorities and field agencies may accordingly be directed so as to prevent any such recurrence in future," it added.A top official of the state government, when contacted, described it "as a routine exchange of information among different government agencies".This was the MHA's third missive to the West Bengal government regarding violation of lockdown measures. The first and the second were sent on April 4 and April 10 respectively.The Union home ministry in its letter on Saturday had objected to what it called was a "gradual dilution" of lockdown in the state and said shops of non-essential goods were allowed to open and the police also gave permission to religious gatherings.