An auto-rickshaw driver who tried to resist the robber was injured in the incident.
A man tried to snatch the bag containing the cash at gunpoint from Sethi when he stepped out of his car.
As Sethi resisted, the man fired a gunshot around his waist and escaped with the cash, Additional Deputy Commissioner of Police Chinmoy Biswal said.
"An auto-rickshaw driver tried to stop the criminal but he too received a head injury," the officer said. The robber escaped on a bike with his associates who had been waiting for him on a street corner.
Sethi, who owns a petrol pump on Aurobindo Marg and lives in Maharani Bagh, was rushed to the Max hospital in Saket where he was said to be out of danger.
The officer said preliminary investigation revealed the accused had been keeping an eye on Sethi, who was on Tuesday carrying three days of cash collection at the petrol pump.
"We are examining CCTV cameras to ascertain the identity of the accused," he said, adding the police suspect that an employee of Sethi may be involved in the crime.
(This story has not been edited by Business Standard staff and is auto-generated from a syndicated feed.)