Three days after serial blasts ripped through Ahmedabad, killing at least 50 and leaving another 150 wounded, Surat’s diamond hub was on the edge today after police recovered and defused as many as 18 bombs.

Diamond shops and factories shut down as bomb disposal squads got down to work, defusing bombs found in the areas of Varachha, Katargam, Kapodara and Mahidharpura.

Surat Police Commissioner R M S Brar, while asking citizens not to panic or fall prey to rumours, appealed to them to remain vigilant and alert the police if they noticed anything suspicious. On his orders, malls, multiplexes, municipal gardens remained closed today.

But Brar failed to explain why his team had no intelligence on the planting of bombs on such a massive scale across the city. On Sunday, the police had discovered a bomb at a traffic island opposite the Nupur Hospital and two cars — they were later found to have been stolen from Navi Mumbai — packed with explosives. On Monday, a bomb was found at a power sub-station at Labheswar Chokdi in Varachha.

Since morning today, bombs were reported from different areas. As many as 12 bombs were recovered from the diamond hub of Varachha, three from Gajera Circle in Katargam, two from Hira Baug Circle in Kapodara and another from Mahidharpura Hira Bazaar.

Forensic Science Laboratory Deputy Director S M Darjee said that the explosives recovered from the two abandoned cars weighed up to 40 kg. “We checked and found that 1 kg of ammonium nitrate was used in each live bomb. These bombs were of high intensity and could impact anything or anyone within 10 feet. The bolts, nuts and spheres could have damaged human organs. The terrorists had not used timer devices but had gone for integrated circuits. Due to some fault in mechanism, the bombs did not explode,” Darjee said.