Intelligence officials say a suspected U.S. missile strike has killed two people in the Pakistani tribal region of North Waziristan.
It was the second time alleged U.S. missiles have rained on the region Thursday.
The missiles hit two homes in the Ambarshaga area, some 15 miles (25 kilometers) west of the main town of Miran Shah. The identity of the victims was not immediately known.
The U.S. is widely thought to carry out missile strikes in Pakistan but rarely confirms the attacks. Pakistan routinely protests them though it is believed to secretly aid in the campaign.
The two officials spoke on condition of anonymity because they were not authorized to speak to media on the record.
THIS IS A BREAKING NEWS UPDATE. Check back soon for further information. AP's earlier story is below.
ISLAMABAD (AP -- Pakistan's president faced fresh calls to step down Thursday after the Supreme Court struck down an amnesty that had protected the increasingly unpopular leader and several of his political allies from corruption charges.
The decision late Wednesday weakened the already shaky rule of President Asif Ali Zardari and sharpened political tensions in the nuclear-armed nation just as the United States and its other Western allies want it to unite and fight militants along the Afghan border.
The U.S. on Thursday was believed to have carried out another missile strike against militants along that border. Intelligence officials said the missiles hit a car carrying two suspected insurgents in Dosali village in North Waziristan, a Pakistani tribal area where the media is largely barred from entering.
The two officials spoke on condition of anonymity because they were not authorized to be identified by name in the media. The U.S. has carried out more than 40 such strikes this year, killing scores of suspected al-Qaida and Taliban militants, but angering many Pakistanis.
While it is generally agreed that Zardari has immunity from prosecution as president, the court ruling means his opponents can now challenge his eligibility to hold the post. Zardari is already unpopular, in large part because of his close ties with Washington. The allegations of wrongdoing being heard in court will add to his troubles.
Zardari's aides said any corruption charges against him were politically motivated and that there was no reason for him to step down. Critics countered he was morally obligated to resign, at least while the court heard any challenges to his rule.
"It will be in his own interest, it will be in the interest of his party and it will be good for the system," said Khawaja Asif, a senior leader from the opposition Pakistan Muslim League party.
The amnesty was part of a U.S.-brokered deal with then-military ruler Pervez Musharraf that allowed former Prime Minister Benazir Bhutto to return home from self-exile and participate in politics without facing charges her party says were politically motivated. Zardari, Bhutto's husband, took control of the party after Bhutto was assassinated in 2007.
Known as the National Reconciliation Ordinance, it stopped corruption investigations and probes into other alleged misdeeds or wiped away convictions in cases involving up to 8,000 ministers, bureaucrats or politicians from across the spectrum.
Civil rights activists have criticized the amnesty as having unfairly protected the wealthy elite.
Zardari has been haunted by corruption allegations dating back to governments led in the 1990s by his late wife. He spent several years in prison under previous administrations. The Supreme Court this week heard allegations he misappropriated as much as $1.5 billion.
The court on Wednesday singled out an investigation that began in 2006 in a Swiss court into allegations of money laundering against Zardari and his late wife. Authorities in Switzerland suspended the case last year after the attorney general under Musharraf told them the government was no longer pursuing it. At the same, Geneva authorities unblocked $60 million that had been frozen in Swiss bank accounts on request of Pakistani officials.
The court said this was illegal and ordered the government to ask Swiss authorities to reopen the case.
Switzerland Justice Ministry spokesman Folco Galli said it had not received any new request for international judicial assistance from the Pakistani government.
He said Pakistan must have an open criminal investigation into Zardari before it can file for Swiss help. If Zardari enjoys presidential immunity, there would be no legal basis for Switzerland to investigate accounts linked to him, he said.
Pakistani papers on Thursday welcomed the Supreme Court decision striking down the amnesty as a victory for justice. Many editorialists said it boded ill for Zardari.
"Zardari: an accused president," read the headline over a front-page story by a well-known critic in The News.
Some analysts said Zardari may be able to take some of the sting out of his opponents' attacks -- and ultimately survive in office -- if he gives up many of the powers he inherited from Musharraf.
A few weeks ago, amid mounting pressure, Zardari relinquished command of the country's nuclear arsenal and said he would soon give up more powers. But that's a promise he's made before, including in a major speech to lawmakers just days after being sworn in.
Also Thursday, a suicide bomber detonated his explosives outside the residence of a district mayor in northwest Pakistan, killing himself and causing some damage to the house, police said. Local police official Habib Khan said the attack occurred in the Lakki Marwat area, which lies about 150 miles (250 kilometers) south of the main northwest city of Peshawar.
It was not immediately clear if the mayor was home at the time of the blast. Militants have frequently targeted political leaders in Pakistan. Earlier this week, a suicide car bombing killed 33 people outside the home of a senior politician in Dera Ghazi Khan town in eastern Punjab province.
Associated Press writer Ishtiaq Mahsud in Dera Ismail Khan, Riaz Khan in Peshawar, and Bradley S. Klapper in Geneva contributed to this report.