"There is indeed a political angle to my husband's murder two days ago as he did not have personal enmity with anyone. But there could also be professional reasons," Mr Ranjan's wife Asha Devi said.
She demanded death sentence to the culprits and vowed to fight till her last breath to get justice.
Mr Gautam urged the state government to bear the cost of education and related needs of Mr Ranjan's children.
"The state government should bear the cost of education and related needs of 16-year-old Ashish Ranjan and his eight year-old sister Sakshi Ranjan as his father will no more be with them to secure their future," Mr Gautam Ranjan told news agency PTI.
The district bureau chief of vernacular daily 'Hindustan', Mr Ranjan was shot dead by unidentified assailants near a fruit market on Station Road in Siwan on May 13.
Meanwhile, BJP took out protest march throughout Bihar while its state unit president Mangal Pandey staged dharna in Siwan demanding arrest of the culprits and a CBI probe.