Govind Pansare was killed in Kolhapur in western Maharashtra in 2015.
The special investigation team of Maharashtra police which is investigating the murder of rationalist Govind Pansare arrested two persons in the case on Saturday.
One of them, Vasudev Suryavanshi (29), had been arrested earlier in Nalasopara explosives seizure case this year, while another, Bharat Kurne (37), had been arrested by Karnataka police in connection with the murder of journalist Gauri Lankesh.
Both were produced before a court in Kolhapur which remanded them in police custody for seven days.
The prosecution told the court that Suryavanshi had arranged the two-wheeler used by the assailants who shot Mr Pansare, while Kurne handed over a used weapon to them.
The SIT had earlier arrested Sameer Gaikwad, Virendra Tawde and Amol Kale in the Pansare murder case.
While Tawde was first arrested by the CBI in the rationalist Narendra Dabholkar murder, Kale was first arrested in the Lankesh murder case.
The CBI had told a Pune court recently that the murders of Mr Dabholkar, Mr Pansare, M M Kalburgi and Ms Lankesh were interconnected.
While anti-superstition activist Dabholkar was shot dead in Pune in August 2013, Mr Pansare, a rationalist and leader of the Communist Party of India, was killed in Kolhapur in western Maharashtra in February 2015.
Kannada scholar and writer M M Kalburgi was killed in Dharwad in August 2015, while Ms Lankesh was killed in Bengaluru in September 2017.