Two suicide bombers killed 43 people in near-simultaneous blasts, the fourth major attack in Pakistan this week and a clear sign that militants have the power to strike targets despite months of army offensives and U.S. missile strikes.
Friday's twin bombings in the eastern city of Lahore, which also wounded about 100 people, raised fears of a new wave of attacks by Islamic militants. With no explanation of why the violence is surging now or how long it could last, Pakistanis have been left to guess at how bloody the situation could get.
"This is an attack against our people, our country," said senior Lahore official Sajjad Bhutta, calling on law enforcement agencies to improve their intelligence networks.
Underscoring the widespread fear, a series of small explosions injured at least three people and sparked panic in another Lahore neighborhood late Friday night. Police officials said the five low-intensity blasts apparently resulted from loose explosives scattered through the residential area of Iqbal Town. While the explosions terrified residents and sent police and rescue workers racing through town, there were no reports of deaths or major damage.
The two suicide bombers, who were on foot, set off their explosives within seconds of each other near two trucks carrying soldiers on patrol in RA Bazaar, a residential and commercial neighborhood with numerous military buildings. About 10 of those killed were soldiers, said Police Chief Parvaiz Rathore.
It was the second major attack in the eastern city of Lahore this week.
Security forces swarmed the area as thick black smoke rose and bystanders rushed the wounded into ambulances. Video shot by a cell phone just after the first explosion showed a large burst of orange flame erupting in the street, according to GEO TV, which broadcast a short clip of the footage shot by Tabraiz Bukhari.
"Oh my God! Oh my God! Who are these beasts? Oh my God!" Bukhari shouted after the blast in a mixture of English and Urdu.
The explosions killed 43 people and injured about 100, said senior police official Chaudhry Mohammad Shafiq.
No group immediately claimed responsibility, but suspicion quickly fell on the Pakistani Taliban and al-Qaida, which have been fighting to destabilize the U.S.-allied Islamabad government.
They launched a bloody wave of bombings last fall across Pakistan, leaving 600 people dead in near-daily attacks done in apparent retaliation for an army offensive against the insurgents' main stronghold, in the tribal region of South Waziristan along the Afghan border.
The government offensive was seen as fairly effective, forcing many Taliban leaders to flee and reducing the area where the insurgents could operate openly.
The insurgent attacks slowed early this year. In recent months, they have been smaller, farther apart and largely confined to remote regions near Afghanistan.
But on Monday, a suicide car bomber struck a building in Lahore where police interrogated suspects - including militants - killing 13 people and wounding dozens. The Pakistani Taliban claimed responsibility.
Also this week, suspected militants attacked the offices of a U.S.-based Christian aid group in northwestern Pakistan, killing six Pakistani employees, while a bombing at a small, makeshift movie theater in the city of Peshawar killed four people.
It remains unclear why the violence is increasing now. It could be in revenge for a series of recent arrests, or, less likely, because of the visit to Pakistan this week by Afghan President Hamid Karzai - a bitter enemy of the Taliban.
Mahmood Shah, a former security chief for Pakistan's tribal regions, long an insurgent stronghold, sees the attacks as violent flailing by semi-independent militant groups who lost many of their leders in the government offensive.
It will be hard, he said, to crush them without better intelligence.
"You can't have a centralized strategy against them because they have no centralized leadership," he said.
But he also doubts insurgents have the resources to launch the same kind of series of ttacks that swept Pakistan last year.
The attacks certainly show the insurgent network has not been crushed despite the recent arrests and regular U.S. missile strikes in Pakistan against Afghan Taliban and al-Qaida operatives. While many of the arrests remain closely guarded secrets, the militants known t have been arrested in Pakistan include the Afghan Taliban's No. 2 commander, Mullah Abdul Ghani Baradar.
The Pakistani Taliban, meanwhile, are believed to have lost their top commander, Hakimullah Mehsud, in a U.S. missile strike in January. The group has denied Mehsud is dead but has failed to prove he'sstill alive, and the attacks could be a way to show they are still relevant.
"The Pakistani Taliban are telegraphing that they are able to strike despite the hits they have taken," said analyst Kamran Bokhari of the U.S.-based security analysis firm STRATFOR, said. "It looks like we are in the middle of a new wave of attacks."