Mukesh Jain and his brother Hemant, who have a jewellery shop in Chandni Chowk area, were returning home to Laxmi Nagar when the incident happened, a police officer said.
They had stopped at a place when three armed men robbed them at gunpoint and fled with a bag containing the jewels, the officer said, adding that the robbers also took away the car's keys which left the duo stranded.
Based on a complaint, police has registered an FIR and launched a manhunt to nab the culprits.