By Faisal Aziz
KARACHI (Reuters) - Shopowners surveyed gutted premises and security forces patrolled nearly empty streets in Pakistan's commercial capital on Tuesday, a day after a suicide bomber killed 32 people and triggered a city-centre riot.
The bombing of a Shi'ite Muslim procession in Karachi underscored multiple security challenges facing the nuclear-armed U.S. ally at a volatile time for embattled President Asif Ali Zardari.
The government launched a security crackdown last October against al Qaeda-linked Taliban militants in their tribal strongholds in northwest Pakistan and retaliatory bombings since have killed hundreds of people across Pakistan.
Karachi Mayor Syed Mustafa Kamal told Reuters the death toll had risen to 32, with dozens of injured still in hospitals.
"We have arrested some people and are investigating," Karachi police chief Waseem Ahmed told Reuters. "According to our initial investigation, the suicide bomber was aged between 18 and 20, and he used 8-9 kilograms of explosives."
He said at least 500 shops and nine buildings had been set ablaze in the aftermath of the attack.
The attack may have just been part of a series of bombings designed to spread panic or an attempt to ignite sectarian violence to pile more pressure on security forces.
"It is clear that the terrorists are very well organised. They want to destabilise the country," said Anjum Naqvi, who was part of the bombed procession.
TRANSPORT IDLE, SHOPS CLOSED
The provincial government of Sindh, of which Karachi is the capital, declared a public holiday, though banks and the stock market remained open. Public transport was out of service and most shops and petrol pumps were shut after religious and political parties called for a day of mourning.
"Our office and the whole building is completely burnt. Everything has been destroyed," said Saleem Khan, who runs a car rental business along what is normally a busy road.
A spokesman for the paramilitary rangers, Major Aurang Zeb, said his forces were "on 100 percent deployment and will take every possible step to maintain peace."
Some grieved before attending funerals, which can be risky -- militants have bombed funerals for their victims, usually in the northwest. Others said their lives had been shattered.
"I know it's a huge loss for the families of those who were killed. But what about our families? We are alive and have lost everything," said Muhammad Shams, owner a shop which makes plastic.
A teeming city of 18 million, Karachi has a long history of ethnic and factional violence, although it has been spared the brunt of Taliban attacks over the past couple of years.
Investors have factored in the violence. But sustained troubles could hurt financial markets in an economy in virtual recession. The Stock market opened over one percent lower.
In Monday's bloodshed, the assailant blew himself up at a march by thousands of people marking the climax of Ashura, the Shi'ite calendar's biggest event, despite heavy security.
The attack was the third in as many days in Karachi.
"Karachi is the heart of the country and any incident here does have a negative impact on investor sentiment," said Mohammed Sohail, chief executive of brokerage Topline Securities.
Aside from al-Qaeda linked militants bent on toppling his government, the president is also under political pressure.
Some of Zardari's closest aides and thousands of members of his party could face renewed corruption charges which could weaken him further at a time when the United States is pushing his government for tougher action against militants.
(Additional reporting by Augustine Anthony in Islamabad; Editing by Michael Georgy and Ron Popeski)
