Friday's drone attack was the first reported strike since Monday's pre-dawn U.S. commando raid that killed al-Qaida leader Osama bin Laden.
Authorities say the attack targeted a compound in North Waziristan, a stronghold of Taliban and al-Qaida militants on the border with Afghanistan.
U.S. drone strikes against militants based in Pakistan's tribal belt have been a source of friction between the two countries and Friday's strike could further inflame tensions between Islamabad and Washington.
Anti-US protests
And, with anti-U.S. protests taking place across the country on Friday, security has been tightened further to quell any potential violence. Several Islamist groups demonstrated Friday against bin Laden's killing, saying more figures like him would arise to wage holy war against the United States.
Speaking to journalists outside the parliament building Friday, Chaudry Nisar, the head of the opposition in Pakistan's national assembly, called on the government to clarify outstanding questions about Osama Bin Laden and the U.S. raid that led to his death.
Nisar says the nation's honor has been trampled by the U.S. raid, and he says and for the government to conduct business as usual is not acceptable. He says someone must be found responsible and heads must roll.
Unpopular drones
U.S. drone strikes are extremely unpopular in Pakistan because of the perception of high civilian deaths from the missile attacks which are targeted militants along the Afghan border. Many Pakistanis feel strongly they are a violation of the country's sovereignty.
The Pakistani government said bin Laden's death was a milestone in the fight against militancy although it expressed objections to the raid which killed him as a violation of its sovereignty.
Mounting criticism
Since the covert mission, there has been widespread criticism in Pakistan about how the government has released information on the raid, and about the presence of Osama bin Laden on Pakistani soil. Many Pakistani's say the raid also exposed weaknesses in the country's defense, something Foreign Secretary Salman Bashir denied on Thursday.
"There is no reason for Pakistanis to feel demoralized," he said. "We are proud of our achievements. We are proud of our defense capabilities. We are proud of our armed forces. We are proud of our track record in anti-terror, which is equal to none. And I think we have to look to the future and not be mired in the past," Bashir said.
Pakistan has denied any knowledge of the al-Qaida leader's whereabouts. On Thursday the army threatened to cut intelligence and military cooperation with the United States if it mounted more attacks on Pakistani soil.
