He lamented that the state had gone back several decades due to the "complete failure" of the PDP-BJP combine there.
"The brutal lynching of Deputy SP Md Ayub Pandith marks a new low. Pained beyond words at the horrific incident," he said on Twitter.
"Heartbreaking to see J&K being pushed back several decades because of the complete failure of the PDP/BJP government," he tweeted.
Gandhi has been on a vacation abroad to meet his grandmother where he also celebrated his birthday.
DSP Mohammed Ayoub Pandit was stripped naked and stoned to death by an irate mob after he allegedly opened fire at a group of people, who caught him clicking pictures near a mosque in Srinagar's downtown area in the early hours today.