At least 81 people have been killed after a bridge collapsed at a tourist spot in India

At least 81 people have been killed after a bridge collapsed at a tourist spot in India.

Children were among up to 500 Diwali sightseers crammed on the century-old suspension bridge when it crashed into the Machchhu River in Morbi, Gujarat, witnesses said.

Rescue workers are battling to save people - including kids - who plunged into the river and those who remain trapped, with many critically injured.

Shocking pictures from the scene show survivors desperately trying to scramble to safety by clambering up the twisted remains of the bridge while others swam to the riverbanks.

Meanwhile, footage shared on social media shows people hanging off the collapsed footbridge and others frantically attempting to cling to the structure.

A survivor of the tragedy, Prateek Vasava, told 24 Hours Gujarati-language news channel he swam to the river bank after falling from the bridge.

Vasava said he witnessed several children drop into the river.

"I wanted to pull some of them along with me but they had drowned or got swept away," he said.

The bridge had collapsed in just a few seconds, the survivor said.

The historical bridge had been closed for renovation work for six months and had only reopened to the public just four days ago.

It may have given way as it could not handle the number of people on it, officials told the Press Trust of India news agency.