The police suspect the killing to be a fallout of professional rivalry, he said.
Last Thursday, when he was going to his factory in an auto-rickshaw, some unidentified persons allegedly kidnapped him and strangled him to death, Katkar said.
The accused later took the body to a forest in Dahanu area here and burnt it by pouring petrol over it, he said.
Katkar said they suspect that Prashant Sankhe got Shaikh killed over some business rivalry.
The Sankhes were arrested from Vapi in Gujarat while Mahajan was nabbed from Jalgaon in Maharashtra, he said.
A woman working at a private firm here was also detained over suspicion as Shaikh had complained to her employer sometime back that she was misappropriating the company's funds, the official said.
The victim's remains were yet to be traced, he said.
The accused were booked under Indian Penal Code Sections 302 (murder), 363 (kidnapping) and 201 (causing disappearance of evidence of offence), he added.
(This story has not been edited by Business Standard staff and is auto-generated from a syndicated feed.)