"Is it a crime to wipe the tears of these people?" Priyanka tweeted attaching a video of the weeping kin of victims of the Sonebhadra carnage.
Ten people, from the Gond tribe, were killed and two dozen injured in a caste clash over a land dispute in Murtiya village in Sonebhadra and Priyanka was on her way to Sonebhadra to meet the victims' families when she was detained at Narayanpur in Mirzapur.
Earlier on Friday morning, she had visited the Trauma Centre at BHU to meet those who had been injured in the Wednesday's massacre in Sonebhadra.
She has been under detention at the Chunar Guest House for last 22 hours, insisting that she would not return to Delhi without meetings the victims. She described the killings as a "massacre" and has refused to fill the bail bond of Rs 50,000.
The Congress leader said that the administration informed her that she was detained under section 107/116 of the CrPC. "I have not done anything wrong and so I will not fill the bail bond. District administration and the government is free to send me to jail if they want," she added.
"The Uttar Pradesh government has sent ADG Varanasi Brij Bhushan, Varanasi Commissioner Deepak Agarwal, Commissioner Mirzapur and DIG Mirzapur to tell me that I should return without meeting the victims' families. They have not given me any reason or documents for detaining me," Gandhi earlier said in a tweet.
"I have made it clear to them that I have not come here to break any law but to meet the families and I won't return without meeting them," she added.
Even while she remained under detention, scores of Congress workers and locals gathered at the guest house to meet her.
The police have arrested 29 people, including the kingpin Yogesh Dutt, in connection with the violence in Sonebhadra. A case has been filed against 78 people.
( With inputs from IANS )