New Delhi } The blast near the Red Fort that killed at least 12 people on Monday may have been caused due to panic and desperation after raids carried out by the security agencies across multiple locations in Delhi-NCR and Pulwama, J-K, to nab suspects believed to be part of a terror module, preliminary assessment by security agencies said.

Senior security sources also said the bomb was premature and not fully developed, thus limiting the impact.

The explosion did not create a crater, and no shrapnel or projectiles were found on the spot, averting a major attack due to "pan-India alertness and coordinated crackdown" on suspect modules, the security assessment said.

Whether it was pre-planned or accidental will be ascertained during the course of detailed probe, the sources said.

Raids by security agencies across multiple locations in Delhi-NCR and Pulwama led to the recovery of significant quantities of explosives, which are believed to have led the suspect to act hastily under mounting pressure, the sources said.

Eight people, including three doctors, were arrested and 2,900 kg of bomb-making material was seized following the busting of the white collar terror module on November 9 and 10.

The suspects did not follow the usual pattern of a suicide car bombing -- neither rammed the car into a target nor collided intentionally, the sources said.

The investigators suspect that the explosion could be accidental rather than a suicide attack.

The terror module appeared to have assembled the improvised explosive device (IED) improperly, leading to the blast in a moving car, the sources said.

The blast took place in a slow-moving car at a traffic signal near Gate No. 1 of the Red Fort Metro station on Monday evening, killing at least 12 people and gutting several vehicles, officials said.