According to the ED, Singh, a 1998-batch IAS, was posted as the Saharanpur DM between March 28, 2012 and February 12, 2014.
On October 8, BJP leader Chaudhary Yashpal Singh was gunned down in a similar manner in Deoband, and two days later, another leader called Kabir Tiwari was killed in Basti.
Of all the districts in India, three were selected for the study to represent low, mid and best female labour force participation.
CM Yogi Adityanath took cognizance of the matter and announced an ex-gratia of Rs 5 lakh each for the deceased.
Congress general secretary Priyanka Gandhi Vadra meanwhile alleged that UP was “in the grip of criminals” with help from the state government.
Congress general secretary Priyanka Gandhi Vadra alleged that Uttar Pradesh was "in the grip of criminals" and the state administration was covering up crimes.
However, the police did try to stop the Congress vice-president but the latter adamantly reached the clash-affected area to take stock of the situation.
Gaurav Yadava, a lawyer, who had filed a PIL in his personal capacity, mentioned the plea for an urgent hearing, saying that the situation in the areas was "critical" and needed judicial intervention.
After a fresh wave of caste conflagration sweeping Saharanpur over the last two days, the situation remained tense but under control on Thursday.
The forces were sent after a request from the Uttar Pradesh government, which also despatched a preliminary report to the Home Ministry with details on incidents of violence.
The Home Ministry has asked the state government to provide details of the incidents which started last month and the steps taken to restore peace in the western Uttar Pradesh district.
Violence erupted for the second day today as unidentified gunmen shot and seriously injured a member of the upper-caste Thakur community, which is embroiled in a bloody conflict with Dalits.
Mobile internet, messaging and other services were also suspended in the district to prevent rumour mongering.
Mayawati, during her visit to Saharanpur, had accused the ruling party with failing to stop its own brigade from attacking weaker sections.
Home Secretary Mani Prasad Mishra said that adequate security deployment has been done.