NEW DELHI, March 15 -- Indian air traffic control experts have ruled out the possibility of the missing Malaysia Airlines jet entering Indian airspace without being noticed by Indian defense system, said local daily Times of India online Saturday.

Air traffic controllers at the eastern Indian city Kolkata have ruled out the possibility of the missing Malaysia Airlines flight MH370 flying over Indian airspace, said the report.

The report quoted the city's air traffic controllers' guild secretary Sugata Pramanik as saying at while flight MH370 could have avoided detection on the Secondary Surveillance Radar, the blip by the huge Boeing 777-200 ER aircraft would surely have been spotted by the Air Force that uses Primary Surveillance Radars to detect such intrusions.

"Any flight that moves in the north-western direction towards Kazakhstan from Malaysia, as suggested by (Malaysian PM) Razak, is bound to pass through Kolkata Flight Information Region. (FIR)," he was quoted as saying.

Razak told a press conference in Kuala Lumpur Saturday that the missing air jet could have taken two possible corridors, a northern corridor from the border of Kazakstan and Kukmenistan to northern Thailand, and a southern corridor stretching from Indonesia to the southern Indian Ocean.

"If an aircraft wants to avoid being seen, they can easily become invisible to a civilian radar by switching off the transponder that relays information about the plane. But it cannot avoid defense systems. The Indian Air Force has radars in multiple installations across the country and it is inconceivable that none of them spotted the odd blip with no flight clearance," Pramanik said.

There are nine Air Defense Identification zones in India that are manned around the clock to prevent an enemy aircraft from violating Indian airspace, according to the newspaper.

Another aviation guild member of Kolkata, Sushil Mondal, also said all hell would break loose if Air Force detected an aircraft that did not have air defense clearance, according to the newspaper.

"Any plane flying through Indian airspace is first required to submit the flight plan and manifest to the air traffic controls in its flight path. This is then relayed to the Air Force for permission," he said.

"There are times when the Air Force finds a blip that does not match a flight plan. That usually happens when flight plans going missing at their end due to a system or link failure. They then immediately contact us for information. If the plane flight plan isn't of suspicious nature, a clearance is granted. Or else, it is asked to return to wherever it came from. In case, we too don't have any information of the aircraft, all hell will break loose and the Air Force may even scramble jets to take the plane down. Nothing of the kind happened last Saturday," Mondal was quoted as saying.

According to the report, Kolkata airport has an Automatic Dependence Surveillance Radar and Controller-Pilot Datalink Communication that enables it to not only trail planes when it is in the radar zone of 60 nautical miles or nearly 120 km and beyond through very high frequency radio, but also through the data link when the plane goes out of voice communication range.

There are large areas in the Kolkata FIR, particularly over Bay of Bengal, that have no radar coverage at present.

A radar has been installed in Andaman and Nicobar Islands but is yet to be commissioned.