MUMBAI, May 13 -- An RTI activist who had repeatedly complained against a quarry in Virar was murdered on Tuesday afternoon after accompanying revenue officials to the site for an inspection. A circle officer was also assaulted during the attack. Police have named quarry owner Mahesh Patil and his son Mayur as accused and launched a search operation. The body of activist Atmaram Patil was found around 12.30pm inside the quarry in Sheergaon. Police said his head had been smashed with a rock during the attack. According to police, officials from the Vasai tehsildar's office had gone to inspect the quarry following complaints by the victim. Atmaram accompanied circle officer Prabhakar Patil and other staff members to show them the disputed quarry area. Soon after they arrived, a group of five to six men allegedly attacked the circle officer, causing serious injuries to his ear. When Atmaram intervened, he was allegedly assaulted with a rock and killed on the spot. Police said Atmaram had been raising objections to the quarry for the past five years, alleging that blasting activity caused tremors and pollution in the village. Deepak Gaikwad, tehsildar, said the quarry was not illegal, but villagers had raised concerns about operations continuing late into the night. "We have to survey the spot whenever we receive an online complaint, which is what our officers were doing today when the attack took place," said Gaikwad. Family members alleged that Atmaram had repeatedly complained to revenue authorities against the quarry operations and had earlier received threats from the quarry owners. They also claimed he had previously been assaulted by Mahesh Patil and that Mayur Patil had threatened him again on Monday night. Police have detained three suspects in connection with the case. "We have registered a murder case and are trying to trace Mahesh Patil and his son, Mayur Patil," said an officer from Virar police station....