Rameshsingh Pardeshi, 58, who was posted at the Crime Branch in Dhule, shot himself in the head with his service revolver in front of his wife at their residence around 12.30 am, Superintendent of Police M Ramkumar said.
Mr Pardeshi had some disagreements with his wife following which the couple had a fight late Wednesday night.
During the heated argument, the inspector shot himself in the head and collapsed, he said.
On hearing the screams of his wife, some police personnel living in the neighbourhood rushed to Mr Pardeshi's residence and took him to hospital where he was declared dead before admission, another official said.
The postmortem was being conducted at the government hospital in Dhule from where the body will be taken to his native place in Nashik for the last rites, the official said.
A case has been registered in connection with the incident.
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