Accusing him of killing a boy by administering a wrong injection about a year ago, three people allegedly murdered a doctor in Odisha's Subarnapur district, police said Wednesday.Two of them have been arrested, while efforts are on to nab the third accused, police official B.S. Udgata told IANS.Udgata said Durbadala Mishra, 51, the additional district medical officer at the district headquarters town of Sonepur, about 280 km from here, was found dead near his home in Sonepur Sunday night with his throat slit.Police said local resident Pratyush Kumar Panda, 24, is the main accused in the crime. He had nursed a grudge against the doctor because he suspected his eight-month-old nephew died due to the latter's negligence.The infant had developed some illness about a year ago and Panda had brought him to Mishra's clinic. The child allegedly died minutes after being administered an injection by Mishra, police said.Panda wanted to take revenge and, as per plan, he along with two of his friends attacked Mishra and murdered him in front of his house. The three accused were drunk, the official added.