Prakash S Bhoir (44) was arrested by Safala police of Thane district in connection with the murder of his second wife and was kept in a lock-up for interrogation, district police said today.
At around 8 pm yesterday, Bhoir complained of uneasiness and was rushed to a local hospital where he died, they said.
Police have registered a case of accidental death and are further probing.
Bhoir, a habitual drinker, was accused of killing his second wife by slitting her throat with a kitchen knife over a domestic issue in Palghar taluka of Thane on April 16, they said.
The accused was booked under sections 302 (murder) and 506 (criminal intimidation) of the Indian Penal Code.
According to the son, his father had killed his step-mother, as she had lodged a complaint against Bhoir's first wife with police, they added.