The incident has been reported from a village near the district town.
Local police's Sub Inspector Mojabber Hossain said that bodies of three children − a boy and two girls − have been recovered on Wednesday morning from the Sadar Upazila's Alokbarhi Village.
The victims are 10-year-old boy 'Yaseen', 'Mariyam', 8, and 'Marzia', 6, he said, adding they were children of one Abul Kamal Mia of the village.
Quoting neighbours, Sub Inspector Hossain told bdnews24.com that Rubel strangled his younger brother and two sisters to death over a family feud.
He had also attacked his other brother Atikur Rahman with sharp weapons when he tried to stop him.
Locals nabbed Rubel and reported the incident to police.
Police have started its investigation over the killings and the bodies have been sent to the state-run hospital in Narsingdi town, said Sub Inspector Hossain.