A 35-year-old man's charred body was recovered from a house in Sharsha upazila of Jashore on Friday.
Badrul Alam Khan, officer-in-charge of Sharsha police station, said that Manirul's body was found inside the house of Sirajul Islam in Kajirber village, where the woman and her husband lived as tenants.
Around 2am on Friday, local people rushed to the house hearing the screams of a man and found Manirul's charred body near his bike. Cops were informed and a team from the local police station rushed to the spot and took the body into custody.
"Local people alleged that Manirul was set on fire in the dead of night over an extra-marital affair with Bithi Khatun, the wife of NGO officer Saidur Rahman," the OC said.
Police have sent the body to Jashore Medical College and Hospital morgue for an autopsy and detained Bithi for interrogation.
"A probe is on," the OC said.