Terrorists fired indiscriminately on the police personnel near the general bus stand Anantnag, the official said.
He said constable Imtiyaz Ahmad was killed while constable Shabir Ahmad was injured in the firing.
The attack took place a kilometre away from the proposed venue of the meeting of the home minister with CRPF personnel on Sunday.
The area has been cordoned off and a manhunt has been launched to nab the attackers.
Rajnath Singh is on a four-day visit to Jammu and Kashmir.
Singh met Chief Minister Mehbooba Mufti in Srinagar on Saturday.
He will also travel to Anantnag, Jammu and Rajouri and meet civil society members, leaders of political and social outfits, business leaders and others, a move seen as a follow-up to the prime minister's Independence Day speech in which he had reached out to the people of the strife-hit Valley.
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