NEW DELHI: After three days of investigation into the blast near the Israeli Embassy here, the Delhi Police is planning to register an FIR as they have found "crucial evidence" pointing to a conspiracy to threaten the envoy, sources said on Friday.

Delhi Police sources said security agency officials are contemplating the charges under which the FIR would be registered.

They are also analysing if the investigation can be handed over to the National Investigation Agency (NIA).

Officials of the Delhi Police, who are investigating the case, have scanned multiple CCTV footage around the site of the low-intensity blast and spotted a suspect who had come from Jamia Nagar in an auto-rickshaw.

They have questioned multiple auto-rickshaw drivers, including the one who brought that suspect to the spot before the blast occurred on December 26.

"We found some crucial evidence suggesting a blast at Prithviraj Road. The way the letter was put at the spot also suggests that there was a conspiracy to threaten the Israeli envoys because of the Israel-Hamas conflict," a police officer privy to the investigations said.

Although no one was injured in the low-intensity blast, an "abusive" letter addressed to the Israeli ambassador was found near the site, officials had said.

According to them, Tuesday's blast and the recovery of the letter is a grim reminder of the 2021 blast near the embassy in which some cars were damaged. The NIA had probed the case.

Investigating officials are awaiting reports from the National Security Group's laboratory where samples have been sent to ascertain the components used in the explosion that occurred in the area between the boundary walls of the house on plot number 4 -- Nanda's House -- and the Central Hindi Training Institute on plot number 2A on Prithviraj Road.

The NSG has a dedicated forensic lab that is trying to find out the components and chemicals used in the blast.

"It may take a few more days to submit the final report," a source said Police sources said they have recorded statements from a dozen people who claimed to have heard the loud noise of the blast.

The statements reveal that the witnesses spotted a vehicle that broke down near the blast location.