New Delhi, Dec. 26 -- Around 40 kgs of explosives were used in the deadly blast near Red Fort, Home Minister Amit Shah said on Friday, while speaking at an anti-terror conference.

At least 13 people were killed after a deadly explosion ripped through a car near Red Fort - in November. The blast occurred near the Subhash Marg traffic signal close to the Red Fort - which involved a slow-moving Hyundai i20 car that exploded.

A special court on Friday extended the custody of two key accused being investigated by the National Investigation Agency in connection with the deadly Red Fort blast case, as the anti-terror agency continues to unravel the larger conspiracy behind the attack.

(This is a developing story. Keep checking for more update...