Umesh Kolhe, 54, was attacked and killed by two men on a motorcycle on June 21.
Umesh Kolhe, a chemist from Maharashtra's Amravati who was allegedly killed for defending former BJP spokesperson Nupur Sharma's comment about Prophet Muhammad, was friends with the accused arrested for his murder, his brother Mahesh Kolhe said on Sunday.
"He was good friends with Yusuf Khan, who is the arrested accused, a practicing veterinarian. We knew him since 2006," Mr Kolhe told news agency ANI.
Khan was among six people who had been arrested for the June 21 murder that was linked to Nupur Sharma's comment on Saturday, amid mounting pressure from the local BJP unit.
Amravati MP Navneet Rana today accused the city commissioner of suppressing Umesh Kolhe's murder. When asked about his views on the police's alleged suppression of the case, Mr Kolhe said that he could not say for sure.
"I am not an expert in these things to say that if they had tried to suppress it or not. What I feel is that they should have used their power a little more and should have treated it with more seriousness ... Perhaps the police did not have adequate evidence to link the case with the Nupur Sharma controversy until now," he said.
The case was transferred to the National Investigation Agency (NIA) by Union Home Minister Amit Shah on Saturday after the local BJP unit accused the police of trying to conceal the reason behind the killing.
Referring to Amit Shah's intervention, Mahesh Kolhe said that it was "unfortunate" that he had to step in.
"It is unfortunate that the Home Minister had to come in and look into the case. If the case had been looked into carefully from the beginning without the Home Minister having to step in, then that would have been better," he said.
Speaking to ANI, he said that since the "mastermind" of the case has been arrested, the pace of the investigation would undoubtedly increase.
"What we wanted to know for a long time was why such a calm person, who had no ill will with anyone, could be murdered in such a way ... Our only demand is that the trial be done in a fast-track court and the maximum possible punishment be given," Mahesh Kolhe said.
Umesh Kolhe, 54, was attacked and killed by two men on a motorcycle on his way back from work on June 21 in Maharashtra's Amravati city. The murder occurred a week before a similar killing in Udaipur.