"Jamaat tried to fuel unrest as elections are nearing," Rangpur Superintendent of Police Mizanur Rahman told reporters after inspecting the scene on Saturday.
He said police identified four people who instigated the attacks following alleged blasphemy and already arrested one of them.
He identified the arrestee as Khaleya union Jamaat-e-Islami Assistant Secretary and Shaleyashah Jam-e-Masjid Imam Sirajul Islam.
The SP said Sirajul along with Jatiyatabadi Olama Dal central committee Organising Secretary and Rangpur district unit President Enamul Haque Mazedi, Sadar Upazila BNP member Masud Rana, and Khaleya union Jamaat member Mostain Billah delivered provocative remarks at a human-chain programme before the attacks.
Jatiyatabadi Olama Dal is a pro-BNP organisation. The Jammat is a key ally of the BNP.
Police raided the homes of the three others on Friday night, but they had already fled, the OC said.
"Jamaat-Shibir carried out the attacks led by them. They are the instigators of the arson attacks, lootings of Hindu homes," SP Mizanur said.
All the 53 detained over the attack and those injured in the clash with police belong to Jamaat, he said.
"They carried out the attack to create instability ahead of the 11th parliamentary election," the SP said.
The programme was organised on Friday in protest against an allegedly blasphemous photo posted by Titu Roy, a Hindu man, on Facebook.
At least nine Hindu families lost their houses in arson attacks while one of the protesters was killed in police firing.
No mercy would be shown to those who would try to disrupt communal harmony, said Awami League Organising Secretary Khalid Mahmud Chowdhury after visiting the scene.
Titu Roy 'illiterate'
One of the houses torched in the attack belongs to Titu Roy, the man who allegedly uploaded the Facebook post.
SP Mizanur said police found no blasphemous post by him on Facebook.
Titu's mother Jiten Bala said he never studied in a school and left the area a decade ago for work.
Titu is accused in a case over the alleged post.
Police have sued over 2,000 people in two cases over the attack.
Sirajul, Mazedi, Masud and Mostain are named as prime suspects in the case.