The government guest house where Congress' eastern Uttar Pradesh General Secretary Priyanka Gandhi was putting up on Friday faced power outage.
The Congress party workers, who were there with her in Chunnar, alleged that the district administration was doing this to force her to leave the place.
Congress workers were also heard shouting slogans against Prime Minister Narendra Modi and Chief Minister Yogi Adityanath.
Yogi-Yogi Hai Hai, Modi-Modi Hai Hai, Yogi Sarkar Hosh Me Aao, Hatyari Sarkar Hosh Me Aao -- were some of the slogans shouted by Congress workers. They also shouted - Jo Sarkar Nikammi Hai, Wo Sarkar Badalni Hai."
"The district administration wants to trouble the Congress workers and force Priyanka Gandhi to go from here. But, no matter how much they trouble us, we are going to be here," said Shiv Kumar Singh Patel, a Congress worker.
"We are going to spend the night in the light of a candle. Congress workers in the entire country are protesting against the way Priyanka ji is being treated," added Patel.
Another Congress leader Gulab Chand Pandey said: "The government thinks if there is darkness, people will go from here. We will not run away. We will not leave our leader. We will be here with Priyanka ji. Such a big incident took place and opposition leader is not being allowed to go there. Is this not the murder of democracy?"
As the guest house faced power cuts, Priyanka was seen interacting with the people and clicking selfies with them.
Earlier in the day, Priyanka was detained and taken to Mirzapur by the state while she was on her way to meet the kin of those killed in July 17 Sonbhadra firing incident, in which nine people were killed.
Talking to reporters here, she said: "When the administration tells me why and on what basis I have been arrested, then I will decide about what I have to do next."
Reacting to a tweet of a senior police officer that no arrest has been made, she said: "No arrest? So, should I go then?"
"I was brought here in the SDM's vehicle. You all were there. I have been told that I should stay here in Chunnar and not go out. If it is not the arrest, then what is it," she asked.
( With inputs from ANI )