Roshan Naresh Ghodeswar (40), a history sheeter from Madhya Pradesh who had settled in a north-west city locality sometime back, raped his 16-year-old daughter in July last year and later sexually assaulted the other 14-year-old girl, police said.
The girls' mother had left Roshan following which he had married another woman.
The girls confided in their step-mother that the accused used to rape them at knife-point, police said.
Yesterday, the victims, accompanied by their step mother, lodged a complaint with Koradi Police who later arrested Ghodeswar.