Police arrested the main accused in a case filed over the murder of a teenager in Kaharol upazila almost four weeks ago.

Shajahan Ali was arrested in his home in Tarapur village on Wednesday but five other accused, who are his family members, were not found, police claimed.

Family of the victim Dhanniram Roy, 16, who was an SSC student, said he was beaten to death because he protested the assault of Dhanniram's mother Parona Bala Roy by Shajahan and his family members.

"Shajahan and his brothers assaulted Parona on the afternoon of June 2 when she shooed away Shajahan's cow from a small piece of land in front of her home where she grew rice seedlings. Dhanniram protested and an altercation ensued," said the victim's aunt Jotsna Chandra Roy.

In the evening, Shajahan and his brother Abul Bashar, uncle Tajul Islam and cousin Anu Ali came back, picked Dhanniram from home, took him to Tarapur Adivasipara Government Primary School premises and beat him up mercilessly, she added.

Masud Rana, a farmer of the village who was among the first few people who noticed the boy lying on the school ground later that evening, told The Daily Star that they took the victim to Upazila Health Complex where doctors pronounced him dead.

The victim's family members, including his mother, aunt and uncle alleged that they had been intimidated and threatened by Shajahan's family since his death.

On June 13, Sarat Chandra Roy, uncle of Dhanniram, lodged a complaint with a magistrate court against six people over the murder.

After an autopsy found that he was killed, the victim's mother lodged a case with Kaharol Police Station on June 27.

The accused were Shajahan Ali, 34, his brothers Abdul Kalam Azad, 43, Abdul Zabbar, 48, Abul Bashar, 38, his uncle Tazul Islam 55 and cousin Anu Ali, 35, of Tarapur village.

Sub-Inspector Touhidul Islam, who is investigating the case, said they were looking for the accused.

Ajit Kumar Mishra, assistant high commissioner of India in Rajshahi, visited the grieving mother in her home in Biroli village yesterday afternoon.