At least 1,500 policemen were deployed in the Orissa capital ahead of a massive rally planned by Hindu groups on Saturday, police said.
Swami Laxmananda Saraswati Sradhanjali Samiti is organising the rally to protest the state government's alleged inaction in nabbing those guilty of murdering the Vishwa Hindu Parishad leader in Kandhamal district.
The state government allowed the organisation to hold the rally, though the central government objected to it for fear that it may raise communal tension.
"We have deployed about 47 platoons of police forces to maintain law and order," Bhubaneswar Deputy Commissioner of Police Himansu Lal said.
Kandhamal district, about 200 km from here, witnessed communal violence after the killing of Laxmananda Saraswati and his aides at the Jalespata Ashram on August 23.
While police blamed Maoists for the crime, Local Hindus alleged Christians were behind the killings and launched attacks on the community. Christian groups have repeatedly said they had nothing to do with the Hindu leader's murder.
The violence left at least 38 people dead and thousands of Christian had to flee to the jungles to escape rampaging mobs.
While some have returned to their homes, more than 10,000 are still living in government-run relief camps in the district.