Pabna Judicial Magistrate Court-1 Judge Md Rashed Hossain passed the order after the investigation officer of the case sought his 7-day remand for interrogation.
Earlier on Wednesday, police arrested Abul Hossain, a local industrialist and owner of Shimla Hospital and Diagnostic Centre.
Subarna Akhter Nodi, 32, district correspondent of private channel Ananda TV, and editor of Daily Jagroto Bangla, an online news portal, was hacked to death on Tuesday by a group of men on her return from her workplace in the district town.
Nodi's mother filed a case with Sadar Police Station against 6-7 people, including Abul Hossain and his son Razib Hossain, over the killing.
Victim's relatives said Nodi got married with Razib one and half years back without the consent of his family.
When Razib divorced Nodi, she filed a dowry case against Razib which is still under trial.