SITE has said the Islamist group claimed via its own news agency that its militants hacked Sanaur Rahman to death with machetes because he "called to Christianity".
It is unclear whether Sanaur Rahman was a Christian himself or whether he was sympathetic to the views of Christians in a majority-Muslim country.
Via its 'Amaq News Agency, #ISIS claimed the murder of a doctor who "called to Christianity" in Kushtia #Bangladesh
— SITE Intel Group (@siteintelgroup) May 20, 2016
Mr Rahman is reported to have been a homeopathic doctor who ran clinics for the poor in the western area of Kushtia.
He was riding a motorcycle to the area with a university professor named as Saifuzzaman when his assailants, also riding motorcyles, blocked his path and murdered him.
Saifuzzaman was also attacked with machetes and is alive in a serious condition.
District police chief Mohammad Sahabuddin Chowdhury told Reuters: "We suspect Islamist militants are behind the attack."
No arrests have been made in connection with the attacks as of yet.
