Two persons were killed and 16 others injured when a portion of an underconstruction bridge of the Delhi [Images] Metro collapsed and fell on passing vehicles, including a bus, in Delhi on Sunday.

Of the 16 people injured, a man has lost a leg while both the legs of another had to be amputated following the accident, which took place on Vikas Marg in east Delhi's Lakshmi Nagar locality at about 7.05 am when workers were lifting a 400-tonne span of the bridge.

The launcher developed some mechanical fault leading to the collapse of the 34-metre-long span, which fell on a Blueline bus, crushing the driver Surender Kumar to death, a senior police officer said.

Chotte Lal (25), a labourer of the AFCONS company, which is undertaking the construction works, was also killed in the mishap, Delhi Metro spokesperson Anuj Dayal said.

Delhi police spokesperson Rajan Bhagat said 16 people were injured in the mishap.

Two trailers, which are being used for launching the span, and two cars were also damaged in the accident, which blocked the two-way traffic on Vikas Marg.

"It is a big shock to us. We are taking it seriously and we have decided for an independent high-level inquiry by three eminent people into the incident," he told reporters.

According to Dayal, seven injured were rushed to Lok Nayak Jai Prakash hospital while two others are being treated at the Hedgewar hospital at Karkadooma.

"I was sleeping and woke up hearing a huge sound. I thought it was an earthquake and rushed outside only to see the bus under the debris," said Anand Kumar, who lives near the accident site.

Meanwhile, the Delhi Metro announced a compensation of Rs 5 lakh for the deceased and Rs 50,000 each for those injured in the collapse of its underconstruction bridge.

"Rs 5 lakh will be given to the families of both, the driver of a blueline bus and the labourer who were killed in the mishap," Dayal told reporters.

He said Rs 50,000 each as ex-gratia will be provided to the injured. "We assure 100 per cent cooperation, support and maximum care for those who are undergoing treatment in hospitals," he said.