A 75-year-old man was found dead Wednesday morning in south Delhi's Freedom Fighter Enclave with a blow to the head, police said. The victim, identified as Satish Bhardwaj, used to live there alone and his two sons reside out of Delhi, they said. Police have arrested two brothers in connection with the robbery-cum-murder, identified as 28-year-old Ravi and 26-year-old Dharmender, who both live in Paryavaran Complex, they said.