Assailants have gunned down a member of banned Jamaatul Mujahideen Bangladesh (JMB) in the district's Sundarganj upazila.
The deceased is Fazle Rabbi, son of Sadakkas Mondol, of Basanterpara village under Jumarbari union.
Police arrested Enamullah Mandal, 50, another JMB member, also an assistant teacher of Jumarbari High School.
The victim's father Sadakkas Mondol told the Dhaka Tribune: “Assailants riding on two motorbikes opened fire on Rabbi at WAPDA Dam sluice gate area in Mamudpur village under Jumarbari Union around 8pm Sunday on his way back home.
“Critically injured Rabbi was admitted to Shaheed Ziaur Rahman Medical College Hospital in Bogra, where he died while undergoing treatment around 1:30am Monday.”
“Enamullah was with my son during the attack. They [Rabbi and Enamullah] left JMB in 2007. Since then Rabbi started a small business in the capital's Konabari area. He came home last Friday to celebrate the eid with family members,” added Sadakkas.
OC Rafiqul Islam of Saghata police station said Rabbi was a fugitive accused in several cases with the police station.
He said: “He might have been killed by his group fellows over economic or internal dispute. We have held Enamullah for quizzing.”
