A madrasa teacher was beaten to death allegedly by a drug addict in Tala upazila of Satkhira on Sunday afternoon.
Police said the attacker was later killed in a mob lynching.
The deceased teacher was identified as Hafez Shariful Islam Gazi, 48, son of Haji Alimuddin Gazi of Harihar Nagar village.
Hafez Shariful was a teacher of Shahpur Dawatul Quran Hafiziya Madrasa.
The attacker, Raju Gazi, 44, son of Khokon Gazi of Shahpurvillage, was also beaten to death by locals following the incident.
According to local sources, drug-addicted Raju was harassing a madrasa student around 3pm.
When Hafez Shariful intervened and asked him to leave, Raju struck him in the head from behind with a wooden stick. Shariful died on the spot after being hit repeatedly.
Immediately after the attack, locals caught Raju and thrashed him to death at the scene.
Main Uddin Islam, officer-in-charge of Tala Police Station, confirmed the incident and said the bodies have been recovered.