Delhi Metro Rail Corp (DMRC) spokesperson Anuj Dayal said no one had been seriously injured and no one was trapped in the debris.

'There is a risk involved during relief operations. Outsiders were not allowed at the site. Now the barricades will be made stricter. We can only request public to stay away,' Dayal said.

On Sunday, the elevated stretch of the Metro track being built to connect central Delhi with Badarpur in the far south collapsed, killing six people and injuring 15 workers.

It was the worst accident in the history of Delhi Metro.

The impact of Sunday's disaster caused a huge crater in the tarred road and burst a water pipe.

And Monday's accident itself took place about two and a half hours after a portion of the launching girder fell from a great height, temporarily halting salvage operations.

The accidents found an echo in the Indian parliament Monday where Urban Development Minister S. Jaipal Reddy praised Delhi Metro's safety record and denied that the company was hurrying to complete the project ahead of the 2010 Commonwealth Games.

DMRC chairman E. Sreedharan quit after Sunday's disaster accepting moral responsibility, but the government did not accept his resignation.