The mood at the sprawling ground Wednesday night was tense after Hazare's aides alerted the crowd about information they had received about the possibility of the 74-year-old being forcibly admitted to a hospital for medical care.
As soon as Hazare announced that people should not to resort to violence and maintain calm, people started forming rings. The slogan -- "Anna hum tumhare saath hai (Anna we are with you)" -- echoed in and outside the ground.
"This is unfair... how can police take him away when he is well," 64-year-old Vijay Basavaraj from Maharashtra asked IANS.
Around 200 people gathered outside the VIP gate of the ground from where police initially planned to take away the anti-corruption crusader. They did not even allow a police vehicle to exit from the gate.
An ambulance parked in the ground was seen coming out early morning Thursday, prompting some people to lie flat in front of the gate. It was only 30 minutes later that the ambulance was allowed to pass.
"No one can take away Annaji," said Dharam Pal, who came from Rajasthan.
"They are not allowing any vehicle to pass, fearing that Anna may be in it," said a constable deputed at the VIP gate.
By about 4 a.m, around 1,000 supporters were left inside the ground. They formed groups and spent the hours shouting slogans and singing bhajans in shifts.
Whenever the slogans got louder, the TV cameras zoomed in.
A few supporters arrived in the morning and performed a yagna (fire ritual) to seek divine blessings for Hazare's health and pray for the passage of the Jan Lokpal bill.
"We have lost faith in government. Now, it's just god who can help them understand common people like us," said 40-year-old Manoj Verma, who came with seven other priests at 5 a.m to perform the yagna.
As the day advanced, supporters again poured in thousands, raising slogans and singing inspirational songs. They also urged the crowd to demonstrate peacefully outside parliamentarians' houses here.
It was another day - with talks on the Lokpal bill and worries over the failing health of Hazare stretching ahead.