The ceremony saw chanting of priests while the converts, wearing skull caps, performed havan (offering in fire). After the ceremony, vermilion dots were applied on their foreheads. Saffron flags were proudly displayed at the event.
The groups that performed the mass conversions claim that the families were originally Hindu and converted to Islam around 30 years ago.
"About 30 years ago, their forefathers had converted to Islam. Now they realise their interests are protected by Hindu religion so they have returned," said Ajju Chauhan, a Bajrang Dal activist.
Some of the converts, picked from a colony of rag-pickers, claimed that they had been lured with incentives like a ration card and other cards that would entitle them to subsidized welfare schemes.
"We were told we will get ration card, Aadhar card, the police will not bother us. We are poor so what do we do?" said one of the converts.
Others like Sufia Begum got emotional and said, "Please forgive me and let us remain Muslims."
However, the groups, which undertook the conversion ceremony, remain undaunted.
"Come to Aligarh on 25th, both Christians and Muslims will be converted under Adityanath's blessings," said Rajeshwar Singh, area chief of the Dharam Jagran Samanvay Vibhagh.
The episode, which has come after days of protests revolving around the 'hate speech' of Union Minister Sadhvi Niranjan Jyoti, has provided the opposition with fresh ammunition. Parliament is scheduled to debate on the rising cases of communal tension on December 17.
BSP chief Mayawati has said that these events were being organised by communal forces and that her party was against it. Rajiv Shukla of the Congress said that this was being done keeping in mind the Uttar Pradesh Assembly polls in 2017.