Crucial last stage in Games security

India is entering the final and most crucial stage of its security preparations to protect the Commonwealth Games.

National pride, the Games' 80-year history and billions in business investment between India and Australia hang on a successful outcome before and during the October 3-14 sporting showpiece.

Concerns about India's ability to prevent an attack were heightened when two Taiwanese nationals were shot outside a popular New Delhi tourist attraction two weeks out from the opening ceremony.

Motorbike attackers opened fire with a sub-machine gun on a tourist bus at a mosque, with the Indian Mujahideen reportedly taking credit for the attack.

Around 100,000 Delhi police, paramilitary forces and specialised commandos will form a blanket over the sporting venues and athletes village but some other parts of the city will remain vulnerable.

Late construction and last-minute fixes to the 17 sporting venues and village have inevitably impacted the security lockdown plans.

Their readiness is crucial to the protection of Australia's largest away Games team and those of the 70 other national teams attending.

And this all amidst the backdrop of allegations of corruption and dodgy building practices and prolonged monsoon rains that brought an outbreak of dengue fever.

Pakistani militant group, Lashkar-e-Toiba (LeT), tops a litany of terrorist organisations that Indian officials consider a potential threat to the Games.

At least 173 people were killed when members of LeT stormed a series of hotels and other nearby premises in Mumbai on November 26, 2008.

Other security concerns include social unrest, separatist threats and rebel attacks that occur frequently but at a rate that is easily absorbed by a country of one billion-plus people.

India's top security official, Home Secretary G.K. Pillai, has previously commented on a lack of threats to the Games in the past few months.

"It's been a little unusual that we haven't picked up much chatter," Pillai told AAP.

"Yes, if you want to put it in one sense, it's too quiet. But it doesn't mean we are letting down our guard at all."

D.R. Kaarthikeyan, a former director of his country's Central Bureau Investigation is one of many security experts advising Games officials.

Indian security forces thwart potential attacks on a regular basis, Kaarthikeyan has said, but they are not usually publicised.

"When something (an attack) succeeds, you can see 99 have been prevented," he said.

"So many are being rounded up, so many have been detected," Kaarthikeyan said.

Games security operations will also include helicopter-borne snipers and four levels of security around the sporting venues, athletes village and other potential targets.

International policy expert Rory Medcalf from the Lowy Institute says terrorists do have an interest in the Games but Indian security forces will likely prevent any major attack on the venues or the athlete's village.

"You could well have terrorists who opportunistically attempt at least a symbolic attack on some other target either in Delhi or in another part of India," Medcalf said.

The Department of Foreign Affairs (DFAT) and Trade has issued "high degree of caution" warnings to Australians considering travel in Delhi and greater India.

At least 14 major terrorist attacks on New Delhi markets, train stations and other public places have occurred since 2000 and resulted in hundreds of deaths and injuries, DFAT says.

DFAT had not altered its travel warning to India for months but the shooting and recent building failures have resulted in updates.

Peter Varghese, Australia's high commissioner to India, concurs with Indian authorities that no credible terrorist threat on the Games currently exists.

"From what we've seen of the plans and preparations for security, they are very thorough," Varghese said.

"At this stage I don't think there's any reason to expect that we would be facing anything like a contingency which would require government-provided evacuation."

International risk consultant Justin Bowden observed late or missing technology during a security reconnaissance trip he conducted in New Delhi in August.

Bowden's team met with ex-Indian intelligence, security managers at key hotels, former deputy commissioners of Delhi's police force and government officials.

"The CCTV is still being rolled out at many events," Bowden said then.

Commonwealth Games Federation (CGF) chief executive Mike Hooper has fought a long struggle with the Organising Committee to the Games over venues.

He demanded occupancy certificates to confirm the sporting venues and athletes' village were safe to occupy.

A July report from the Indian government's Central Vigilance Commission (CVC) stated some of the venues may have included substandard work that was approved with forged test results.

Indian officials missed two deadlines in August to refute the claims and provide the occupancy certificates but eventually delivered them to the CGF in early September.

Following the footbridge collapse which injured more than 20 people on September 21, Hooper said he had no choice but to accept the documentation as bona fide proof that the venues are safe to occupy.

"We have to accept that they've done their job," he said.

Hooper is satisfied with a final security report he received in September from the CGF's consultant Intelligent Risks that states India is implementing all necessary plans and precautions.

"It's not pretending there's more work to do because there is and the Games haven't started yet," Hooper said.

"You can have the best planning in the world but it comes down to actually what happens on the ground at the time, and ensuring that appropriate security is in place to keep it safe and secure."