Party workers staged a demonstration near Cubbon park this morning, police said. They then damaged the board carrying the name of Sangliana, elected from Bangalore North, and burnt his effigy besides pelting stones.

Meanwhile, Karnataka Chief Minister B S Yeddyurappa ordered police bandobast for Sangliana and said he would issue directions for taking action against those who take law into their hands.

He was responding in the Legislative assembly to leader of the Opposition M Mallikarjuna Kharge (Congress), who condemned the 'attack' on Sangliana's office and 'stone-throwing' there.

Kharge said he received information that BJP activists were involved in the attack and demanded their immediate arrest and police protection to the MP.

Sangliana, former city police commissioner, had earlier said he had cast his vote for the UPA, in keeping with his 'inner conscience' and since he believed that India needed nuclear energy "because power is the lever to development of the country".