The accused identified as Ranbir and Nikhil have confessed their crime, they said.
The body of Hariram (50) was found at Ganga Barrage here on October 6 last year with eight injuries marks inflicted by sharp weapon, SSP Shalabh Mathur said.
The victim allegedly had an illicit relationship with another woman, he said.
The deceased's son, Ranbir has confessed that he was annoyed with his father who was an alcoholic and often used to create ruckus at home, and hence decided to kill him, Mathur said.
They are been interrogated and further investigations are underway, said Mathur.