Around 30 people, including law enforcers, were injured in the clash at Thakurparha village in Khaleya union on Friday afternoon, police and doctors said.
Rangpur Medical College Hospital Assistant Director Shafiqul Islam said 11 people hit by rubber bullets and shotgun shells were brought to the government-run facility.
Seven of them were in a critical condition after being hit by bullets in the head and stomach, Shafiqul said.
The protesters spoke to the superintendent of police and gave the law enforcers 24 hours to arrest the youth.
As their demand was not met, they took out another procession on Friday afternoon and attacked the Hindu homes, Rafiqul said.
Gangacharha Police Station OC Zinnat Hossain said the attackers torched the houses of the nine families in a 'planned manner'.
He said personnel from Kotwali Police Station and Taraganj Police Station joined his forces to keep the situation under control after hearing that thousands started demonstrating on Friday afternoon.
He also said a local grocer on Oct 29 started a case against the Hindu man who allegedly posted a blasphemous photo on Facebook.
Police went to the Hindu man's house but could not find him, the officer said
Assistant Superintendent of Police Saifur Rahman said seven policemen injured in the clash were admitted to the local Police Hospital.
The victims of the arson attacks said hundreds of attackers burnt their houses down.
"We couldn't save anything," said Jiten Bala, an elderly woman. newa