While two live bullets were recovered in the first case, one round was found from the second passenger.
Two people were apprehended by CISF personnel at the Chandni Chowk metro station for carrying bullets in their luggage in Delhi, officials said on Friday.
The two passengers, a 21-year-old man and another aged 17, were intercepted in separate incidents at the station on Thursday during security checks, they said.
While two live bullets were recovered in the first case, one round was found from the second passenger.
Carrying arms and ammunition is banned inside the metro network.
As the passengers could not furnish government authorisation for carrying the bullets, they were handed over to the Delhi Police for investigation, they said.
The Central Industrial Security Force (CISF) is tasked to secure and provide counter-terrorist cover to the Delhi Metro network in the national capital region.