Revathy (35), wife of Palanisamy, and her son, Vignesh (6), were allegedly murdered at their house at Senthil Nagar here on Wednesday evening.
A stone, which was reportedly used by the accused to hit the two on their heads, were found lying beside the bodies.
People in the vicinity first noticed the bodies lying inside the house and immediately informed Palanisamy, who works in a garment unit.
The Anupparapalayam police are investigating.