According to reports, 40-year-old Omveer, the president and deputy leader of Meerapur city unit of BJP was killed by two bike- borne assailants.
The incident happened when Omveer, a retired army man, had gone out for a morning walk, when two assailants fired multiple shots at him with country-made pistols at around 7 am at Monty crossroad, injuring him fatally, police officials said.
Singh too fired from a licensed revolver he was carrying, injuring one of the attackers.
The criminals fled the spot taking away Singh's revolver, they said.
The body has been sent for post mortem.
His killing sparked protest by party workers and Singh's family members.
Senior police officials, who reached the spot, assured the protesters of speedy investigation in the case. Security personnel have been deployed in the area.
"Nothing has been revealed about Vijay Pandit's death, now Omvir Singh died. What is UP CM doing? BJP wont take this calmly", Laxmikant Bajpai, BJP head of Uttar Pradesh told a news agency.
This is the second incident in two days when Dadri Nagar Panchayat Chairman Geeta Pandit's husband Vijay Pandit, a 27 year old young leader was shot dead in Dadri area of Greater Noida.
Four persons were on Sunday detained for questioning in connection with the murder of Vijay Pandit even as police clamped prohibitory orders in Gautam Budh Nagar district.
Pandit was shot dead by four assailants following which his supporters torched 16 vehicles near Dadri police station and pelted stones at a police team.
Pandit's wife Geeta alleged that he was killed due to election rivalry at the behest of local SP leader Narinder Bhati, who denied the allegation.
(With PTI inputs)