MUMBAI, May 14 -- The Virar police have arrested stone quarry owner Bhalchandra Patil and one of his associates in connection with the murder of Right to Information (RTI) activist Atmaram Patil on Tuesday afternoon. The accused were arrested on Tuesday night, hours after the RTI activist was bludgeoned to death while accompanying circle officer Prabhakar Patil and his colleague Pandurang Thakare for an inspection of the quarry in Shirgaon. On Wednesday, family members and relatives of the deceased activist staged a protest outside Virar police station, demanding strict action against the perpetrators. His son Hemant Patil said his father had filed several complaints because the stone quarry was causing noise pollution as well as cracks in their houses. "While we were constantly subjected to threats, no action was taken on the complaints lodged by my father," the grieving son told reporters. Mahesh Patil, the quarry owner's son and the main accused in the case, is absconding along with several other accused while the condition of circle officer Prabhakar Patil, who was grievously injured in the attack, is critical, police officers familiar with the matter told Hindustan Times. As reported by HT on Wednesday, Atmaram Patil, 54, had accompanied Prabhakar Patil and his colleague for a site inspection on Tuesday afternoon. While they were there, several unidentified assailants attacked them with wooden sticks, iron rods, and stones, leaving them critically injured and bleeding profusely. The attackers then vandalised the government vehicle and fled the scene. The RTI activist and the two revenue officers were rushed to a hospital by local residents, where doctors pronounced Atmaram Patil dead. The Virar police subsequently registered a first information report (FIR) against quarry owner Balchandra Patil, his son Mahesh Patil and their associates Pratap Patil, Niketan Patil, Kiran Patil, and one unidentified employee, under sections pertaining to murder, causing grievous hurt, obstructing government employee from discharging his duty, assault on a public servant and other offences. Teams from Virar police, the crime branch, and forensic experts also seized blood samples, broken wooden planks, stones, and damaged vehicle parts from the crime scene, along with CCTV footage from the surrounding area. Suhas Bavche, deputy commissioner of police, Virar, said while the owner of the mine had been arrested, search was on for the remaining accused. Senior inspector Lalu Ture said the attack appeared to be premeditated, and a special team had been constituted to identify the perpetrators. "Several suspects are currently being interrogated," Ture said. Meanwhile, the RTI activist's murder has sparked widespread outrage. On Wednesday, his family members demanded that a separate case be registered for his murder and legal action be initiated against the accused under sections pertaining to murder, obstruction of government duty, and organised crime. The Right to Information Federation, a group comprising around 150 RTI activists, also demanded a thorough inquiry into the matter, and raised questions about why the revenue officers had taken the deceased along during the site inspection, and if there was an entry in the official register regarding the same. President of the federation Mahesh Kadam said circle officer Prabhakar Patil should also be named as a co-accused in the case. Revenue department employees in the area also demanded immediate arrest of the accused and called for enhanced security for government officials. According to local residents, the Shirgaon area has long been embroiled in controversy because of illegal excavation and activities of mining mafias. Though they have lodged multiple complaints with the Vasai tehsildar regarding the use of dynamite in mining operations, mining mafias have managed to stall administrative action by resorting to pressure tactics and intimidation, residents said....