Rakesh Mishra, the Commonwealth Games’ chief engineer, said a loose pin on the bridge’s steel structure had given way whilst “concreting” of the road beneath was in progress.

He said an inquiry has been ordered into the accident which he admitted was a “setback” but claimed the damage would be rectified “soon”.

Mishra also dismissed speculation that the continuous monsoon downpour over the past two days was responsible for the accident.

Preparations for the Games that end on Oct 14 are down to the wire and the event risks descending into farce with large scale construction work on various sporting venues still under way.

In an emergency move the Cabinet Secretary K M Chandrashekhar has now been put in charge to complete the Games’ preparations.

Games officials said all incomplete work would be finished with 36 hours and would be up to “world class” standards.

A few months ago the watchdog Central Vigilance Commission had accused the Organising Committee of shoddy construction of many Games venues and claimed that questionable completion certificates had been granted them.

Organising committee head and ruling Congress Party MP Suresh Kalmadi, however, dismissed these allegations, reiterating that the event would be the “best ever, even better than the 2008 Beijing Olympics”.

But Michael Fennel, head of the Commonwealth Games Federation, issued a damning statement after the athletes’ village was inspected by several participating nations who were “shocked” by what they saw.

“Many nations that have already sent their advance parties to set up within the village made it abundantly clear that, as of the afternoon of Sept 20, the Commonwealth Games village is seriously compromised,” Fennel said.

Toilets in the athletes’ village were leaking and choked and did not flush, building debris was piled high in bedrooms and bathrooms and wiring in residential rooms was incomplete.

Power was erratic or simply not working, several lifts were non-functional and the area around the games inundated with water from the rain and a breeding ground for dengue and malaria-carrying mosquitoes.

“The reality is that if the village is not ready and athletes can’t come, the implications are that it’s not going to happen,” New Zealand’s chef de mission Dave Currie said.

Scottish team officials joined the chorus of condemnation surrounding accommodation for athletes decrying the Commonwealth Games village as “unsafe and unfit for human habitation.”

Team Scotland were reallocated accommodation after lodging a complaint with Games organisers last week but have disclosed that even their new quarters required “serious cleaning” – which they ended up performing themselves.

Security too was a major concern after two Taiwanese tourists were shot and injured by gunmen on a motorcycle reportedly from an Islamist group in Delhi’s walled city area on Sunday.

Several Islamist organisations with links to al-Qaeda had threatened to disrupt the Games. Armed Maoists insurgents too were active across India.

Senior police officials conceded that varied security measures like close circuits televisions, ‘boom’ barriers restricting vehicular movement and other associated equipment was being installed./