BJP's Anil Parihar and his brother Ajit were killed in Kishtwar in the Jammu region on Thursday night.
Two personal security officials of the senior Bharatiya Janata Party (BJP) leader, who was killed along with his brother by suspected militants in Jammu and Kashmir's Kishtwar, were detained today, officials said.
A Special Investigation Team (SIT) has also been constituted by the Jammu and Kashmir government to probe the incident, they added.
BJP state secretary Anil Parihar, 52, and his brother, Ajeet Parihar, 55, were killed on Thursday night when they were returning home after closing their shop, officials said.
The police has detained two personal security officials -- Om Prakash and Sahil Kumar -- who are being questioned, Senior Superintendent of Police Kishtwar Rajinder Gupta said.
Mr Parihar had been given these two officials for his security, but at the time of the attack they were not accompanying the leader, he said.
The tragedy could have been averted had the officials been with him, the police said.
"The SIT has been constituted by police to probe the killings. It is headed by Assistant Superintendent of Police Prabeet Singh," Deputy Commissioner Kishtwar Angrez Singh Rana said.
"We urge all the political leaders and protected persons to keep their PSOs (personal security officials) with them and do not allow them leave them unguarded," he added.
The army staged a flag march in Kishtwar today.