The teenage vegetable vendor, Samiul Alam Rajan, was tied to a pole and beaten up for nearly 30 minutes until he died due to the torture while one of the attackers filmed the gruesome incident and uploaded it on his Facebook page.
Rajan, son of a driver, screamed for help, cried for water and begged for his life while the killers laughed and jeered at him in the 28-minute video of the July 8 incident in Kumargaon of northeastern Sylhet Sadar Upazila following allegations that the teenager had stolen a rickshaw van.
Two of the prime suspects, one of whom 22-year-old Muhith Alam was chased and caught by the locals, have been taken into custody. A manhunt is underway to nab the remaining two.
The people in the neighbourhood had caught Alam as the attackers tried to dump Rajan's body secretly in a secluded place and handed him over to police while the rest fled.
"We brought him to our custody for interrogation in line with the court order," said Akhtar Hossain, officer in charge of the local police station.