Gunmen attacked worshippers from a minority Muslim sect in two mosques of the eastern Pakistani city of Lahore on Friday, taking hostages and killing at least 70 people, officials said.
The gunmen opened fire shortly after Friday prayers and threw what could have been grenades at two Ahmadi mosques in residential neighbourhoods in Pakistan's cultural capital.
Sajjad Bhutta, deputy commissioner of Lahore, said at least 70 people had been killed in the twin attacks on mosques in Garhi Shahu and Model Town. A total of 78 were injured.
The death toll at Garhi Shahu was higher, Bhutta said, because three attackers blew themselves up with suicide vests packed with explosives when police tried to enter the building.
Police are still searching the area as two attackers were still at large.
Punjab Chief Minister Shahbaz Sharif said the incidents would generate greater resolve to combat extremism.
"It's a reminder to the nation that Pakistan will achieve its destiny only after we get rid of the worst type of extremism and fundamentalism," he told a news conference. "The entire nation will fight this evil."
He said one attacker had been arrested. Police in Model Town confirmed one gunmen had been arrested and another killed.
There was no immediate claim of responsibility, but suspicion quickly fell on the Pakistani Taliban.
"It's too early to say who is behind these attacks," said a Lahore-based security official. "But my guess is that like most other attacks, there would be some link to the Taliban or their associated militants."
Punjab's Law Minister Rana Sanaullah said the arrested attacker was a teenage Pashtun, an ethnic group making up the majority in parts of northern Pakistan and Afghanistan. This, he said, indicaed a link to the Pakistani tribal area of Waziristan and strongly hinted at a Taliban link.
"The prayer leader was giving a sermon when we heard firing and blasts. Everybody stood up and then two gunmen barged into the mosque and sprayed bullets," Fateh Sharif, a 19-year-old student, told Reuters from Model Town.
"They had long beards. They were carrying rucksacks."
Bhutta said a suicide vest laden with explosives was recovered from the Model Town mosque, where some attackers escaped. One fired at a television van before the area was made safe.
"He was young, clean-shaven. He sprayed bullets at our van while fleeing the scene," Rabia Mehmood, a reporter for Express Television, told Reuters.
ATTACKS LAUNCHED AFTER PRAYERS
Witnesses said the assaults were launched shortly after prayers.
"I saw some gunmen run towards the Ahmadis' place of worship and then I heard blasts and gunfire," Mohammad Nawaz, a resident, told Reuters.
Stock market investors shrugged off the latest violence.
"Initially we saw some selling after the attack but investors started accumulating shares at lower levels," said Asad Iqbal, chief executive at Faysal Asset Management Ltd adding that there was foreign buying which boosted local confidence.
The Karachi Stock Exchange (KSE) benchmark 100-share index was up 0.75 percent at 9,511.75 points at 4:05 p.m. (1105 GMT).
Ahmadis are a minority Muslim sect founded in the late 19th century. They hold unorthodox beliefs among Muslims, including that Jesus Christ survived the crucifixion and died in Kashmir. Some also believe that prophets have come after Mohammad, the founder of Islam, but that he retains his primacy.
Pakistan is the only Muslim state to have declared Ahmadis non-Muslims. Its 4 million-odd members have seen their religious rights in overwhelmingly Muslim Pakistan curtailed by law.
Pakistan, a key U.S. ally in the fight against militancy, is often the scene of sectarian violence, with militants from Sunni Muslim groups attacking Shi'ite Muslim and Christian communities.
Separately, security forces battled Taliban militants in the Orakzai region near the Afghan border in the northwest and about 40 militants were killed and 30 wounded in attacks by government aircraft in three places, a paramilitary force officer said.
There was no independent confirmation of the toll. Militants often dispute government accounts.
Government forces have stepped up attacks in Orakzai in recent weeks after winding up offensives in several other areas.