Tuesday's specific attack on an Israeli vehicle using an 'antique' device has left security agencies flummoxed. There was no intelligence input about the strike, even vaguely hinting at a sinister plot designed to send ripples through central Delhi's VVIP enclave on Monday afternoon.
The high-intensity blast that left four persons -- including an Israeli diplomat's wife -- injured just 300 metres away from the Prime Minister's residence, was an 'alien attack' in more ways than one.
"We had no advisory or any specific intelligence input about this or any other attack on Israeli citizens or installations. The device used to trigger it is unlike anything used in an attack on the city ever before," said a senior police officer.
The last time the police were asked to keep an eye on both, the officer claimed, was when David Coleman Headley was subtly noticed receding the Chabad House and other potential targets prior to the 26/11 attack in Mumbai.
"The planter took less than a minute to intercept and plant the bomb on the vehicle as it waited at a red light signal. The target was specific - which means that he must have been waiting for the car to arrive," the officer said.
Sources said the 'sticky bomb' that blew up 42-year-old Talyeshova Koren's Israeli Embassy-owned vehicle on Aurangzeb Road was manufactured on the lines of 'Limpet Mines', which were first used during World War II.
"Such bombs were usually magnetic and mainly used to sink ships at harbour. While the probability of the bomb having a magnetic base - because of which it got stuck to the metallic surface of the Innova -- is highest, there is a very slight chance that it was Velcro-based," the officer said.
Prima facie investigations, sources said, point out that the device was compact and contained a 'sophisticated explosive', the nature of which is difficult to guess.
Both ammonium nitrate and RDX have been ruled out at the moment, pending a forensic examination.
According to sources, the bomb did not have a timer but did have an arming switch and destruct mechanism wired to explode within five to 10 seconds after its planter pressed the switch to arm the device before sticking it onto Koren's vehicle.
"There was no shrapnel in its composition, at least none has been recovered," the officer said.
The explosive, police said, seemed to be of 'extremely high quality' since the glass windows of several nearby houses were shattered.
"We have registered a case and are currently in the process of ascertaining the nature of explosive(s) used to trigger the blast. Assistance from various sources will be taken and given as required," said Dharmendra Kumar, special CP (law and order).