Rana took the decision as he apprehended that violence might erupt and thus result in law and order problem, endangering life and property of citizens of Kistwar town.
Police had announced curfew in Kishtwar, Doda and Baderwah, besides imposing prohibitory orders, banning assembly of more than four people in Ramban, Banihal, Poonch, Kathua, Rajouri and upper reaches of Gool Gulabgarh.
This is the first attack on any political leader in the Jammu region in past several years, PTI reported.
The killings of Parihar brothers drew severe condemnation from all quarters.
Union Home Minister Rajnath Singh expressed shock and pain over the killings, saying the police will leave no stone unturned to bring perpetrators of the crime to justice.
"Shocked and pained by the killing of J&K State BJP leader Anil Parihar and his brother. My heart goes out to the bereaved family," he said in a tweet.
The home minister also spoke to K Vijay Kumar, the advisor to the Jammu and Kashmir Governor, and took stock of the incident.
"Spoke to Advisor to J&K Governor, Sh Vijay Kumar regarding the incident. The police will leave no stone unturned to bring the perpetrators to justice," he said.
In a tweet, former Chief Minister Omar Abdullah said it was a "very sad news" and offered condolences to the families of Parihar brothers.
"Very sad news. My condolences to Anil & Ajit Parihar's family & colleagues. May their souls rest in peace," he said.
BJP general secretary Ashok Koul condemned the attack and called for punishment to the culprits involved in it.
CPI(M) MLA MY Tarigami and state Congress president Gulam Ahmed Mir also condemned the killings of the BJP leader and his brother.
Mir termed the attack "barbaric and unfortunate" and pointed towards the deteriorating law and order situation in the state.
National Conference's Jammu province chief Devender Rana strongly condemned the killings as "barbaric, inhuman and most unfortunate".
"Violence has no place in a civilised society," Rana said and hoped that the people will unitedly face the challenge posed by elements inimical to peace and tranquillity.