Followers of the Muttahida Qaumi Movement (MQM), march at a protest in Karachi on July 14. (Rizwan Tabassum/AFP/Getty Images)

A two-year-old government effort to restore order in this Pakistani port city has halved the notoriously high murder rate, but security officials’ tactics have intensified confrontation with a powerful political movement that vows it won’t easily be subdued.

In 2013, as Karachi endured a record 2,789 homicides and a number of bombings, Prime Minister Nawaz Sharif ordered paramilitary forces known as the Pakistan Rangers into the city. Their goal was to reverse decades of lawlessness spawned by mafia groups, Islamist militants and drug cartels that had long jockeyed for local control. But one particular target has been gangsters, some of whom were ­suspected of links to the city’s ultra-influential Muttahida Qaumi Movement (MQM).

According to MQM leaders, 4,000 of their supporters have been arrested over the past two years, with some saying they were tortured for crimes they did not commit. Now, Pakistani forces appear to be cracking down on the secular party’s long-standing practice of soliciting donations from businesses to help fund its vast charitable network.

The high-stakes question for Sharif’s government is whether the Rangers can cement the security gains in the city of 20 million without triggering more ethnic and cultural division.

“We are passing through some of the most difficult times of our history, challenging times, as the government and the military establishment have turned against us,” Muhammad Farooq Sattar, head of diplomatic affairs for MQM, said earlier this month in an interview at the party’s compound in Karachi. “MQM is being pushed to the wall.”

Twelve hours later, at dawn on July 17, Rangers stormed the party’s offices, the second such raid in four months, and arrested two senior leaders. Rangers have also plucked MQM workers and sympathizers from their homes and offices.

On the surface, MQM is just another vibrant political organization serving voters who feel oppressed — in this case, mainly Muslims known as Mohajirs who migrated to Pakistan from India during the 1947 partition that established the separate countries. But MQM workers and followers have also been accused of hundreds of murders over the years, part of what analysts and officials say has been an orchestrated attempt by the party to also use force to carve out — and keep — a grip on Karachi’s affairs.

The MQM leaders, who report to the group’s bombastic founder, Altaf Hussain, insist that they eschew violence. But they don’t deny that some of their supporters, acting independently of the organization, may have been involved in illicit activity over the years.

Whatever the case, Karachi today is a much safer place than it was.

The city recorded 1,823 homicides last year, about 1,000 fewer than in 2013, according to police statistics. That decline is continuing this year, with 554 killings reported from January through July 21.

In a sign of improvement, Karachi retail outlets reported record sales during the recent Islamic holy month of Ramadan.

Pakistani paramilitary officials escort blindfolded MQM political party to a court in Karachi in March. (Rizwan Tabassum/AFP/Getty Images)

“The people of Karachi are taking a big sigh of relief,” said Arif Alvi, a lawmaker from the Movement for Justice Party, which has been trying to cut into MQM’s support in Karachi.

For MQM followers, however, the ongoing security operation is opening a fluid new chapter in what they describe as their ­decades-long struggle to fit into a country under the sway of a few wealthy families. Even some of the party’s rivals say the Rangers need to be mindful of potential consequences.

“Any misstep by security forces that might seem political rather than fighting criminals will have a disastrous fallout,” said Farhatullah Babar, a senator from the Pakistan People’s Party, a group often at odds with MQM. “Instead of resolving a problem, it will invite a self-destructive crisis.”

About 7 million Urdu-speaking Mohajirs migrated to Pakistan during the partition, and most settled in Karachi and surrounding areas of Sindh province. They say they have been repeatedly marginalized by ethnic Punjabis, Pashtuns and Sindhis with roots in the areas that became Pakistan.

Hussain, who lives in England, tapped into those grievances to rapidly build a dominant political organization with a platform of tolerance, secularism and moderation.

Supporters treat Hussain like a king; his picture is plastered on lampposts, doorways and car windows near MQM headquarters in central Karachi. The group, which claims to serve as an antidote to Islamist extremism in the city, is backed by a force of 100,000 political workers.

During the 1990s, both Sharif, serving a previous term as prime minister, and the late prime minister Benazir Bhutto supported crackdowns on MQM amid street battles between it and rival groups. The military ruler who followed them, Pervez Musharraf, maintained an uneasy truce with the group during his tenure from 1999 until 2008.

With the party again feeling under threat, MQM leaders warn that Karachi could face a new period of crisis.

“The more pressure we face, the more they squeeze us, the more people will get upset,” said Ali Raza Abidi, one of 35 MQM lawmakers in Pakistan’s Parliament. “I will be honest and say, ‘This is racism, and it’s discrimination.’ ”

On Thursday night, after Abidi was interviewed by The Washington Post, the Rangers raided a popular seafood restaurant that he owns in Karachi, storming in and seizing video monitoring equipment, according to MQM officials. On Friday, the Rangers issued a statement saying that in the raid they had picked up a person who is a suspect in 10 murders, Pakistani media reported.

Of the 4,000 MQM sympathizers who have been arrested over the past two years, 750 remain behind bars, according to Sattar. Forty more have died in extrajudicial killings, and 20 are missing, he said. In addition, he said, 200 have been the victims of targeted killings by rival groups.

Shuman Saleh, a 47-year property dealer and MQM supporter who was arrested in September but never charged, claims Pakistani Rangers confined him in a small wooden box for 10 days.

“I was brutally tortured and humiliated,” Saleh said. “They were asking me, ‘How much murder have you done and for whom did you collect [money]?’ ”

Adnan Habib, 30, said the Rangers took him and his younger brother from their home near Karachi University, an MQM stronghold, in May. He was also held for more than a week but never charged, he said.

“First they beat us without any reason, and then afterwards, they asked, ‘How many murders do you admit to?’ ” Habib said. “I said, ‘I am a normal worker who just does preparations for elections.’ . . . They said, ‘If you are married, we will make you impotent.’ ”

Spokesmen for the Pakistan Rangers, the Interior Ministry and the army refused several requests for comment.

But many retired Pakistani army officials and political leaders defend the Rangers, saying the drop in homicides demonstrates that MQM sympathizers were responsible for a big share of Karachi’s past violence.

The Rangers “are arresting criminals across the board,” said Masud ul-Hassan, a retired brigadier and member of the Pakistan Ex-Servicemen Association.

At times, the government’s confrontation with MQM has appeared to be just another sideshow in a country where political theater and paranoia are common.

In mid-July, Hussain gave a speech railing against the Rangers and accusing them of corruption. Since then, Pakistanis have filed more than 100 criminal complaints alleging he slandered the Pakistani military — taboo in a country that has lived through three military coups but still reveres its armed forces.

“He has badly damaged the political image of that party,” said Abdul Qayyum, a sitting senator and leader of Sharif’s Pakistan Muslim League-N party.

In June 2014, British authorities arrested Hussain at his house in London and charged him with money laundering. He remains free on bail awaiting trial.

Pakistani authorities also appear to be clamping down on MQM’s access to money.

For years, the party has solicited donations — which critics say amounted to shakedowns — from Karachi-area businesses to fund charitable efforts that include a hospital, ambulance service and cash payments to needy families. This year, however, the Rangers are threatening businesses with arrest if they contribute, resulting in a 75 percent drop in donations, Sattar said.

But some analysts predict the Rangers’ actions may end up helping the party. In the past, when the Mohajir community feels threatened, it has rallied behind MQM candidates, said Muhammad Amir Rana, director of the Islamabad-based Pak Institute for Peace Studies.

“If they are trying to disrupt MQM, they instead may just give it another lease on life,” he said, noting that an MQM candidate easily won a special election for a Karachi-area seat in the National Assembly in April.

Sattar can’t guarantee, however, that MQM workers will remain focused solely on politics in the coming months. Fifteen thousand workers now in hiding will eventually emerge in search of money and support, he said.

“If you have this mind-set that we are responsible for every problem,” he said, “then where do we go from here?”

Haq Nawaz Khan in Peshawar and Shaiq Hussain in Islamabad contributed to this report.

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