The national capital was on Friday put on a high alert in the wake of blasts in Maharashtra's textile town of Malegaon.
Security has been stepped up at all vital installations and places of worship, while checking has been intensified at all entry and exit points.
A tight vigil is also being maintained at crowded places including railway and bus stations, cinema halls and market places.
"We have alerted our personnel," Police Commissioner KK Paul said.
Police have also asked the public to inform the police immediately in case they find any suspicious object.