A huge fire is seen on a stage during a cultural event in Mumbai, India, Feb 14, 2016. [Photo/Xinhua]

"We were shaken with the sudden announcement that there has been a fire at the venue but thankfully there were multiple exit routes," said Heman Goyal, a Delhi businessman who was attending the event.

"There was chaos but we all got out in time. I saw parts of the stage burning."

The blaze is likely to overshadow the message of India being open for business that Modi wanted to send. When he opened the investor jamboree on Saturday, Modi called Make in India "the biggest brand India has ever created".

The prime ministers of Sweden and Finland took part in Saturday's gala opening ahead of Make in India Week, which is being attended by 2,500 foreign companies and 8,000 firms from India.