The person arrested is the owner of the car that is said to have been used by the accused for the crime.
Attacking Prime Minister Dr Manmohan Singh for opposing its proposed flag hoisting at Lal Chowk in Sringar, the Bharatiya Janata Party on Sunday accused the Centre and the state government of "surrendering" to separatists who have declared that they will not let the tricolour be unfurled.
The killing led to tension and protests at several places in the coastal district on Wednesday with instances of stone-pelting and police lathi-charge.
Dwivedi, son of BJP's district unit president of Allahabad Ramraksha Dwivedi, had reportedly announced a reward of Rs 1 crore for chopping off the tongue of Owaisi and called the AIMIM chief a 'traitor' who has no right to live in India.