Habibul Mia, 52, a physically disabled and speech-impaired wheelchair user, died at Dhaka Medical College Hospital on the afternoon of August 3.
He was from Baruha, also known as Rajghat, village in Tarail upazila of Kishoreganj.
Police and local residents said unidentified assailants attacked him at about 2:30am while he was sitting in his wheelchair on an unpaved road in front of his home.
They alleged that the attackers struck him on the head with a piece of wood and took the money he had with him.
Local residents took him to Tarail উপজেলা Health Complex after hearing him cry, police and local residents said.
He was later referred to Dhaka Medical College Hospital as his condition worsened.
His cousin Alamgir Hossain said Habibul had long used a wheelchair and earned a living by begging at the Tarail CNG station.
Alamgir Hossain filed a murder case on the morning of August 3 against two or three unidentified people, Tarail police chief Sheikh Abu Saleh Masud Karim said.
Police said they had started investigating and were trying to identify the people involved.
No suspect identities, arrests, forensic findings or formal account of the cause of death were provided.