Jammu and Kashmir Liberation Front chairman Mohammad Yaseen Malik, Democratic Freedom Party president Shabir Ahmad Shah and five others were taken into preventive custody on Friday, just before they were to start their campaign to boycott civic polls in the state.
They were stopped at Mirgund on the Srinagar-Baramulla National Highway when they were heading for Kupwara, sources said.
The JKLF, DFP, Kashmir Bar Association and Jamiat-e-Ahlihadees last week appealed to the people to boycott the polls.
Municipal elections are being held in the state for the first time after 27 years, beginning February 1, 2005.