Investigation has revealed that apart from the i20, which blew up near the Red Fort, the suspects also had another red car.
The Delhi Police has sounded an alert across all police stations, posts, and border checkpoints in the national capital to trace a red Ford EcoSport car suspected to be linked to the Red Fort blast that claimed nine lives.
The Delhi blast is the most significant security incident since April 22, when 26 people were killed at the tourist site of Pahalgam in Jammu and Kashmir.
The alert was issued after the investigation revealed that other suspects, already connected to the Hyundai i20 used in the explosion, were also in possession of another red-coloured car, sources said.