The government hailed the temple as a sign of Pakistan’s growing tolerance under Prime Minister Imran Khan. But pressure from clerics mounted, and the government gave in.

A Hindu temple planned for Islamabad, the city’s first, was supposed to be a symbol of tolerance. Instead, violence and controversy have turned it into an emblem of Pakistan’s troubled relationship with its religious minorities.

When Pakistan’s former government allotted land for the Shri Krishna Mandir, or Krishna temple, in 2018, Muslim demonstrators quickly camped out on the plot, refusing to allow a Hindu structure to be built in their nation’s capital. But the temple’s Hindu advocates seemed to prevail, and when the temple’s first foundation stones were laid last month, government officials proclaimed it marked the start of a new, tolerant chapter for Pakistan. Days later, Prime Minister Imran Khan ordered the government to provide about $1.3 million for the temple’s construction, roughly a fifth of what is needed.

“When we broke ground, the prime minister told us in a meeting that he was quite happy that the temple would give a good image of Pakistan to the outside world,” said Lal Chand Mahli, a Hindu parliamentarian and member of the governing party, the Pakistan Tehreek-e-Insaf.

“A Hindu temple in the capital,” he added, “was going to show the world that Pakistan is a place for all religions.”

Then Muslim clerics stepped in again, and things started changing.

Several clerics ruled that no Hindu temple should be built, because Pakistan is a Muslim country. Citizens denounced the government for using their taxes to provide funding for the temple. And media outlets openly campaigned to shut the project down.

Under mounting pressure, the government on Friday backtracked from its initial pledge to donate money to the temple’s construction, instead asking for guidance from the Council of Islamic Ideology on whether to give the grant.

The government then halted construction of a wall being built around the temple’s empty plot of land, ruling that the complex’s blueprint had to be approved first. Islamabad’s Hindu council claimed that the wall was necessary to keep vandals out, and that they worried that Muslim extremists would try to occupy the land and delay the temple’s construction as they had before. Similar barriers protect empty plots of land across Pakistan, they argued. But the government held firm.

The fever pitch around the temple finally erupted on Sunday when a group of men destroyed the partially constructed wall around the temple’s land, claiming it was their Islamic duty to do so. They gleefully filmed their exploits and posted it on social media. None of the vandals have been arrested.

In a matter of two weeks, the hope surrounding Islamabad’s first Hindu temple was derailed, as were any aspirations that the government of Mr. Khan would deliver on the religious coexistence he had promised when he won elections in 2018.

While the plan for the temple was approved in 2017 under the former government, Mr. Khan put the plan into action and received praise for what many had hoped would mark a new, more tolerant chapter in Pakistan’s violent sectarian past.

During Mr. Khan’s election campaign, he promised to improve conditions for Pakistan’s religious minorities, often treated as second-class citizens and targeted in attacks by violent Islamists with few repercussions. He also vowed to restore their places of worship.

Mr. Khan seemed to make good on his promise late last year when the government reopened one of Sikhism’s holiest shrines, the 500-year-old Gurdwara Darbar Sahib Kartarpur. The government hailed the reopening as proof of their religious tolerance at a time when Pakistan’s neighbor and archrival India was marginalizing their Muslim minority.

On Tuesday, Amnesty International condemned the campaign against the Hindu temple and urged the government to allow the Hindu council to resume building immediately.

“Prime Minister Imran Khan must lend his commitments to religious freedom for all some weight and ensure that Pakistan’s Hindus and other religious minorities are able to practice their faith freely and without fear,” said Omar Waraich, the head of Amnesty International’s South Asia department.

“Every reported act of violence against minorities must be promptly investigated and those responsible must be brought to justice. A recurrence can only be prevented if adequate measures are taken,” Mr. Waraich added.

Although Hindus are between two and four percent of Pakistan’s population, Islamabad does not have a temple for them to worship in. If their relatives die, they must travel long distances with the body to Hindu-run cremation facilities to perform traditional burial rites.

Founded as a state for South Asia’s Muslims, Pakistan had a secular, democratic Constitution crafted by the father of the nation, Muhammad Ali Jinnah, who is still revered across the country. But the partition of the Indian subcontinent in 1947 unleashed a wave of violence between Hindus and Muslims that both nations have not recovered from, decades later. Neighbors turned on each other to cleanse their villages, towns and cities of Hindu or Muslim minorities. Although estimates vary, up to 2 million may have been killed in the violence.

Amendments to the Constitution, followed by a wave of Islamic radicalization within the powerful armed forces, have seen Pakistan morph into a considerably more sectarian nation than Mr. Jinnah had envisioned.

“Pakistan is a religiously diverse place and people of different religions live in the country. Islamabad is our capital and all religions have equal rights in it,” said Mr. Mahli, the Hindu parliamentarian. “Jinnah promised our rights would be upheld when the country was created.”