Braving mosquitoes and the heat, some of the suspended MPs like CPI's Santosh Kumar, AAP's Sanjay Singh spent the night beside the Gandhi statue in Parliament complex.
TMC's Dola sen and Santanu Sen were present on the site till post midnight with no permission for a tent granted by the authorities, five MPs slept under the sky as a protest against the suspension of 24 MPs, 20 from Rajya Sabha and four Congress members from Lok Sabha.
"50 hour non-stop dharna by Opposition MPs. 21 hours done. 29 hours to go. Revoke suspension of 24 MPs. Discuss," tweeted TMC Rajya Sabha MP Dwrek O'Brien.
In the morning, TMC MP Mausam Noor who brought tea for the MPs said that the Opposition MPs will not apologise and the protest will continue.
The opposition has demanded a discussion on price rise in both Houses of Parliament.
(Except for the headline, this story has not been edited by NDTV staff and is published from a syndicated feed.)