Jain, 43, was a veteran freelance reporter, who had worked in the field for more than 20 years. He was based in Chhattisgarh state and worked for Hindi-language dailies including Hari Bhoomi, Nayi Duniya, and Dainik Bhaskar.
Jain's body was found the morning after he had left his home to visit a weekly market in Nama village in Sukma district, according to news reports. He had been stabbed to death.
Immediately after Jain's death, police said they suspected Maoists were responsible for the murder and said pamphlets at the scene said Jain was killed because he was a police informer. Police did not comment on allegations that he was an informer.
A week after Jain's death, blogger Kamal Shukla wrote that Jain had not been on good terms with local police and cited the journalist's frequent coverage of false complaints filed by local police against villagers. Shukla denied the possibility that Jain may have been a police informant, according to The Hoot, a South Asian media watchdog. But Shukla also said that Jain's social activism may have led to his murder. A week before his death, Jain had been instrumental in helping free an individual allegedly held by Maoists, and this may have angered the Maoists, Shukla said.
The president of the Chhattisgarh Union of Working Journalists, NRK Pillai, told The Hoot that there was the possibility that Jain may have been pressured by the police to provide information.
Other local journalists, including Anil Mishra, correspondent for investigative magazine Tehelka, said they believed local criminals could be responsible for Jain's murder. A few days before his death, the reporter had exposed tin smuggling in the region, which led to a violent confrontation between the journalist and family members of an alleged smuggler.
Almost two months after Jain's murder, news accounts reported that a local Maoist group had claimed responsibility for the attack, but did not offer a motive or further details.
Journalists in Chhattisgarh are often caught in the tension between Maoists and police and security forces, CPJ research shows. Maoists have led an insurgency in the central tribal areas of India for more than four decades.
Jain is survived by his wife and mother, according to local journalists.