In the preceding weeks they and their peers had acted as informers, police officials say, helping them identify thousands of Muslim-run butchers' shops that have since been shut and urging officers to stop Muslim youths talking to Hindu girls in the street.
Their organization is the Hindu Yuva Vahini (Hindu Youth Force), a private militia set up in 2002 by Yogi Adityanath, a local priest and politician, to assert the dominance of India's main religion which he felt was being eroded by minority faiths.
Since Adityanath's promotion last month to chief minister of Uttar Pradesh state, home to 220 million people of which a fifth are Muslims, the group has become emboldened, openly proclaiming its Hindu roots and putting pressure on police.
The appointment of the 44-year-old, known for his fiery anti-Muslim rhetoric and a campaign against "Love Jihad" - or the conversion of Hindu women to Islam - has shocked some Indians, who say it undermines the country's secular status.
They worry that Prime Minister Narendra Modi's "development for all" agenda will be overtaken by radical, Hindu-first policies with the potential to stoke communal tensions that have erupted sporadically through India's 70-year history.
Adityanath declined to be interviewed for this article.
"Blood can be shed, and Muslims will feel the pain," Pankaj Singh, a senior leader of the Hindu Youth Force, told Reuters in an interview on the sidelines of the rally in Unnao, an hour's drive southwest of the capital Lucknow.
Such comments have sent a chill through some in the Muslim community, on the defensive in Uttar Pradesh since this year's election in which Adityanath rallied the Hindu majority and delivered a resounding victory to the ruling Bharatiya Janata Party (BJP).
In return for his successful campaign, the party handed the priest one of India's most powerful positions, emboldening his militia to act and speak more openly than it did under the previous administration.
Based in Uttar Pradesh and funded by members who want to win favor with local power brokers, the youth force says it is 2 million strong and growing.
In Unnao, police stood back as members blocked traffic, honked horns and shouted pro-Hindu slogans on the busy streets. Muslims who came out to watch did so quietly from their doorways.
HINDU RIGHT, HINDU RADICAL
Modi himself is the product of the Hindu right, coming from the BJP and its powerful parent movement, Rashtriya Swayamsevak Sangh (RSS), that nurtured him early in his career.
But since sweeping to power in 2014, he has focused on economic reforms that he hopes will drag India into the modern era and create enough jobs for a swelling workforce.
Adityanath represented the BJP during the Uttar Pradesh state polls earlier this year, and helped Modi consolidate power as he bids for re-election in a national ballot in 2019.
The priest, however, has often defied BJP discipline and is not part of the RSS machine, raising fears that Modi may have unleashed radical "Hindutva", or religious-nationalist forces that he will struggle to contain.
"The BJP has no command over this organization. They respond to Adityanath and no one else," said Gilles Verniers, assistant professor of political sciences at Ashoka University.
A close aide to Modi said it was Adityanath's job to maintain law and order in the state.
"The onus lies on him. It is his duty to take care of his vigilante group," said the aide.
Daljit Singh Chawdhary, additional director general of police for Uttar Pradesh, dismissed the threat of the youth force acting outside the law.
"We are not tolerating any vigilante group taking the law into their (own) hands, while at the same time anyone is free to provide us with tip-offs," he said.
"We have had no recent complaints against the Hindu Yuva Vahini, so there is no reason for us to take action against them."
DEVOTION AND POWER
The original source of Adityanath's power is an ancient temple in Gorakhpur, eastern Uttar Pradesh, where people treat the shaven-headed priest with reverence.
Soon after he was named chief minister last month, a devotee collected dust from the rug on which Adityanath had walked, so as to worship it.
Built on such devotion, the youth force has evolved into a powerful group that dispenses justice and has proved itself a formidable vote-getter.
The BJP's national spokesman, Nalin Kohli, said the party's victory in Uttar Pradesh was not only thanks to Adityanath and his private militia. But Singh expressed little doubt about the group's importance in securing the result.
"Modi won Uttar Pradesh because of Adityanath's ground force," Singh said.
One of Adityanath's first directives after becoming chief minister was to impose a ban on Uttar Pradesh slaughterhouses that operated without licenses.
Most Indian states have laws that ban the slaughter of cows, considered sacred by Hindus, while buffalo slaughter requires permission from state governments.
Butchers in Uttar Pradesh have long complained that authorities failed to issue new licenses, although the outgoing government allowed them to continue operating anyway, ensuring employment and food for the Muslims who dominate the industry.
Adityanath's militia has been pushing police to enforce rules calling for a complete ban on illegal slaughterhouses and the sale of meat from unlicensed shops.
"We got the police to shut down 45,000 small meat shops in less than 24 hours ... they would have failed without our informers," said Singh, who added that he reported daily to Adityanath. "They (police) know we are the real heroes now."
Chandani Qureshi, a mother of four, said her husband worked as a sweeper in a meat shop in Lucknow. Her family relied on his daily wage of 300 rupees ($4) to survive.
"The chief minister's men came with orange flags, broke the window panes of our shops and threw knives and weighing scales out on the street," she said, sitting in her one-room home. "We had no power to stop them."
Owners of large abattoirs have sought injunctions to block Adityanath's orders to ban unlicensed slaughterhouses and thousands of butchers have protested against the ban, yet some doubt they will prevail.
"I don't think we can defeat Adityanath's militia. It would be better if we start selling something else," said Mohammed Faizan, who inherited a meat shop from his grandfather.
Uttar Pradesh's deputy chief minister and state BJP president, Keshav Prasad Maurya, said his government would not let slaughterhouses sell cow and buffalo meat. It wanted shop owners instead to start selling chicken and eggs.
"The dairy business is more profitable than the beef trade," he said.
He also said members of Adityanath's militia were acting as responsible citizens. "It would be wrong to consider them as a parallel administration."
"HANDS OFF HINDU GIRLS"
At the rally in Unnao, Singh stood on a rickety stage and awarded idols of Hindu gods to youths for halting sales of beef, stopping religious intermarriage and composing poetry in honor of cows.
As well as helping to close down butchers, the militia has been tipping off "Anti-Romeo Squads", groups of police who intervene to prevent young men and women meeting publicly.
A police official who oversees 64 such squads said the units were formed to tackle sexual harassment of women, but admitted that there had been cases where militia members pressured policemen to target Muslim men seen in the company of Hindu women. He declined to be named.
Muslims say they are being singled out.
"They think our boys are villains," said Irshad Sheikh, whose son was detained by police recently.
Singh, the youth force leader, rejected suggestions that the squads deliberately targeted Muslims.
At the rally, he met the father of a 21-year-old Hindu woman who was recently forced by members of the militia to call off her wedding to a Muslim man.
"For centuries, Muslims have been playing the dirty game of converting Hindus," Singh said, as his men returned from their run through the Muslim neighborhood. "But now if they touch a Hindu girl, we can fight with our swords."
The woman's father, Subhash Chandra, said he welcomed the militia's intervention.
"The Muslim boy trapped her and wanted to convert her. I am lucky that Yogi Adityanath's people saved my daughter's life. How can a Hindu become a Muslim? It is a sin to convert anyone."
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