Many enthusiastic BJP supporters had climbed the makeshift marquee during the rally. Modi -- who visited the hospital later -- briefly stopped his speech and was heard repeatedly asking them to get down, officials said.
Giving details of the incident, eyewitnesses added that some people clambered on top of the marquee, which was covered with tarpaulin. The structure could not withstand the weight of the people and collapsed, leading to several in the gathering, including women, being injured, they said.
According to officials, the prime minister saw the tent collapsing while he was in the middle of his speech. He immediately instructed special protection group (SPG) personnel standing near him to look after the people and attend to the injured.
Most of the injured were admitted to hospital, an official said, adding that their number could rise.
Chief Minister Mamata Banerjee said that the state government would provide all medical assistance to those injured in the rally.
"We pray for the speedy recovery of all those injured at the Midnapore rally today. The government is giving all help for medical treatment," Banerjee wrote on her Twitter handle.
(This story has not been edited by Devdiscourse staff and is auto-generated from a syndicated feed.)