A deadly attack on Monday in India on a Muslim family accused of illegally slaughtering a cow has brought attention to growing levels of Hindu extremism in the country, an issue that watchdogs have been sounding alarms about for years.

"I cannot say I am surprised," said Zahir Janmohamed, a former advocacy director at Amnesty International who writes about Indian society.

The attack occurred in Dadri, a village on the outskirts of the Indian capital of New Delhi. Word reportedly spread in a Hindu temple that Mohammad Ikhlaq, 50, had killed and prepared beef in celebration of Eid al-Adha, when Muslims slaughter an animal in recognition of Abraham's willingness to sacrifice his only son, Isaac, to God.

"They dragged my brother and father outside the room and used bricks which they found under his bed to beat them. My father was taken outside the house and beaten to death," said 18-year-old Sajida Ikhlaq, according to the newspaper Indian Express. "They also tried to molest me and hit my grandmother on her face. They threatened to kill me if I said a word to the police."

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Reports said 200 people attacked the household. Mohammad Ikhlaq died, and his 22-year-old son is now in the hospital.

Slaughtering cows, a holy animal for Hindus, is illegal in the Indian state of Uttar Pradesh, where Dadri is located. Sajida claimed the meat that rioters found in her family's refrigerator was mutton.

"The police have taken it for examination," she told Indian Express. "If the results prove that it was not beef, will they bring back my dead father?"

Police reportedly arrested six people, and are now searching for another four alleged assailants. Security forces have flooded into Dadri to keep the peace, but they've clashed with demonstrators who are calling for prosecutors to seek the death penalty against participants in the mob. A demonstrator was reportedly shot in the chaos on Tuesday.

The lynching was only the latest flare-up of Hindu extremism and violence in India in recent years under Prime Minister Narendra Modi, a nationalist who has promoted Hinduism despite India's official secularism. Since he took office last year, Modi has often said Hinduism is not a religion but a "way of life" that should influence policy.

Under Modi's Bharatiya Janata Party, or BJP, officials have banned books that don't jibe with their interpretation of Hinduism, advocated educational curricula that reflect Hindu nationalist themes — like how stem cells were discovered in ancient Sanskrit texts — and imposed harsh jail terms for possessing beef.

Those official policies have arguably emboldened Hindu groups like the Rashtriya Swayamsevak Sangh, a private group associated with the BJP, to get impoverished Christians and Muslims to convert to Hinduism. Modi took months to condemn the controversial conversions.

"He's careful not to incite violence or say things that are actively discriminatory towards minorities," said Ginni Ishimatsu, a Hinduism expert at the University of Denver. "But individuals are encouraged by the Hindu nationalist trend to go after people whom they think are doing things wrong."

Modi's role in the three-day-long riots in Gujarat in Western India in 2002, when Hindu gangs massacred hundreds of Muslims, has fueled skepticism about his agenda. Modi was governor of Gujarat at the time. A government investigation into the riots cleared him, but critics say he sanctioned the violence with a wink and a nod.

Janmohamed, the former Amnesty International advocacy director, witnessed the riots in Gujarat and is now writing a book about their aftermath. He said the recent Dadri lynching appeared to stem from the same hatred that he saw during the violence 13 years ago.

"The Gujarat police often raided the Muslim ghetto where I lived in and reported on, an area known as Juhapura, because there were rumors that a kabob seller was cooking beef instead of lamb," said Janmohamed. "Sadly this mindset appears to be spreading to other parts of India — the idea that India needs to be cleansed of its 'beef eaters,' which is really just code for saying that it needs to be cleansed of its Muslims, its Christians, and even its Hindus who do not follow the Hinduism that Hindu nationalists espouse."