The Somangalam police arrested two men on Sunday for hurling a Molotov cocktail into a vacant house in Varadarajapuram the previous night.
Charles, 24, and Rajkumar, 23, were taken into custody after the incident in MGR Street. The Tambaram police said a couple had recently vacated the rental property and moved to Tambaram.
The two men arrived on a two-wheeler and threw the device into the empty house. It caused minor damage to a wooden door and a cot.
During questioning, police learned that the suspects are relatives of the former tenant Divya. They are married to her sisters and acted out of a personal grudge, unaware that the house was unoccupied.