The incident took place near Raj Nagar extension on Saturday morning when a woman and her son were waiting for a bus to Dehradun at the Mohan Nagar halt.
Having been unable to find a bus for some time, they hopped into a private car when they saw the driver was inviting passengers to Dehradun. Another woman, going to the same place, got into the car with them.
After travelling for about a kilometre, the driver threatened them, took their cash and fled.
"We have received the complaint and an action will be initiated," said Senior Superintendent of Police Vaibhav Krishna.
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