New Delhi [India], January 17 (ANI): Delhi Police has not made any breakthrough in case of the bomb recovered from Ghazipur flower market in East Delhi ahead of Republic Day celebrations, even after three days of continuous investigation.

Officials of the National Investigation Agency (NIA) on Monday met with senior special cell officials of the ongoing probes linked with Pakistan's ISI.

A senior officer with Delhi Police Special cell said that the investigation revealed that explosives recovered were linked to ISI.

"The IED recovered in Gazipur is similar to IEDs recently recovered in Punjab that was smuggled into the state from Pakistan. In recent times, more than 40 sightings of drones were spotted in Punjab border with Pakistan," he said.

The officer said that they have activated informers to get leads regarding sleeper cells who have planted the bomb outside the flower market in Gazipur.

"The nature of explosives recovered in Delhi, suggests that it was transported to Delhi from Punjab through the network of sleeper cells. We are putting many mobile phones and IP addresses on surveillance to get any leads regarding sleeper cells," he added.

"We have rounded up several suspects and a team visited Tihar jail to question terror suspect lodged in jail to get any clue about people involved in the case," he added.

Delhi Police Special Cell and other units are investigating the case to trace the people behind planting a huge quantity of explosives at the busy flower market in Ghazipur.

So far, police have rounded up several suspects and scanned footage of more than 80 CCTVs but failed to get any leads in the case.

The National Security Guard (NSG) on Monday also submitted a report to Delhi police regarding explosives. The report mentioned that a timer run by battery, ammonium nitrate and RDX were used in the IED found at Ghazipur. The total amount of explosives found was 3 kg.

Police recovered an Improvised Explosive Device (IED) from the Ghazipur flower market on Friday. Police rushed a bomb disposal squad and fire engines to control the situation after getting the information.

A case has been registered in the Delhi Police Special Cell under provisions of the Explosive Substances Act. (ANI)