ADIL JAWAD
Associated Press

KARACHI, Pakistan (AP) — British police arrested one of Pakistan’s most well-known and divisive politicians Tuesday on suspicion of money-laundering, sparking fears of violence in his power base of Karachi where businesses closed early and residents rushed home.

Police in Britain do not name suspects until they are charged. But when asked about Altaf Hussain, the Metropolitan Police said a 60-year-old man had been detained Tuesday morning at a residence in northwest London. An official with his Muttahida Qaumi Movement in Karachi, Faisal Subzwari, confirmed the arrest.

Hussain, who is 60, heads the Muttahida Qaumi Movement, or MQM, one of Pakistan’s major political parties that often has been accused by opponents of using violence to bolster its power.

He has lived in self-imposed exile in Britain since 1992 but regularly addresses large gatherings in Pakistan by telephone. He is known for stirring speeches that can whip his followers into a frenzy.

Hussain’s arrest sent shockwaves through Karachi, Pakistan’s largest city. The teeming metropolis, a port city of more than 18 million people, is vital to the country’s economy, and any blowback from Hussain’s arrest could have serious repercussions for Pakistan as a whole.

Immediately after news of his arrest aired on television, residents started shuttering their businesses and going home, fearful of possible violence.

In 2010 another MQM politician, Imran Farooq, was stabbed to death in a daylight street attack in London. The slaying triggered riots in Karachi, where the party has its biggest base of support. No one has been charged over the killing.

Mohammed Atiq Mir, chairman of the All Karachi Trade Association, said all markets in the city had closed. The British diplomatic mission in Karachi was temporarily closed, and the U.S. Embassy in Islamabad warned American citizens of the possibility of protests and unrest in the city. The embassy said it was cancelling appointments for visas and American citizen services at the Karachi consulate on Wednesday.

Pakistan Railways halted train service in Karachi and the rest of Sindh province for three hours. In the past, demonstrators in Karachi have torched railway cars.

“My wife informed me of the arrest of Altaf Hussain, and everybody in the bank wanted to go home as soon as possible,” said Tariq Ali, a banker in Karachi.

Sobia Ahmed, who was waiting for her brother to pick her up, said her mother had called her and demanded she return home immediately.

“We are all aware of the history of this city,” Ahmed said. “After a major incident the city panics, and agitators rule the streets and roads.”

A senior MQM official, Nadeem Nusrat, called on party supporters to remain calm. “We appeal to all the workers to control your emotions,” he said.

But despite the appeal there were reports of scattered violence across the city, senior police officer Pir Muhammed Shah said. He said some vehicles had been burned and there were reports of people firing guns into the air.

MQM condemned the violence and said in a statement that the people behind it were not related to the party.

Authorities have beefed up security at various parts of the city and at diplomatic missions, Shah said.

Nusrat said Hussain had been feeling unwell and was about to go to a hospital for medical tests when London detectives arrived at his home with a search warrant Tuesday.

The MQM, formed in 1984, largely represents descendants of Urdu-speaking migrants from India who settled in Pakistan when it was created in 1947. The party portrays itself as a moderate and secular force. But it has often been accused by competitors of using violence against opponents.

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Santana reported from Islamabad. Associated Press writers Jill Lawless in London and Asif Shahzad and Zarrar Khan in Islamabad contributed to this report.

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