Pakistani officials angered by the secret U.S. raid that killed Osama bin Laden declared they would conduct a full review of operations by U.S. drone aircraft over the country and rebuffed an appeal by visiting U.S. officials not to close military intelligence liaison centers, U.S. and Pakistani officials said. Secretary of State Hillary Rodham Clinton visited Islamabad on Friday in a bid to ease the mistrust deepened by the secret May 2 raid that killed the Al Qaeda chief. Clinton, in a meeting with President Asif Ali Zardari, Prime Minister Yousuf Raza Gilani, army chief Gen. Ashfaq Kayani and other leaders, emphasized that the U.S. has seen no evidence that anyone in the upper echelons of Pakistani leadership knew of Bin Laden's presence in Abbottabad. Officials on both sides described Friday's meeting as blunt, and acknowledged that serious disagreements remained. But they said the two sides also agreed that the relationship is mutually beneficial. A senior U.S. official in Washington said that Pakistani officials rebuffed a U.S. request not to close the liaison offices in Peshawar and Quetta that have been used to share intelligence on militants with Pakistani ground forces, reported The Los Angeles Times. Pakistan recently ordered U.S. special operations personnel at the so-called "intelligence fusion cells" to leave the country, a setback for U.S. efforts to form closer ties with Pakistani units fighting militants along with the border with Afghanistan. U.S. officials remain hopeful that they can persuade Islamabad to allow the U.S. personnel to reestablish the intelligence-sharing centers, the official said. Pakistani officials said Zardari also said his government intended to review all aspects of operations by unmanned U.S. drone aircraft. The campaign of drone airstrikes is deeply unpopular among Pakistanis. Operating from a base in Pakistan, the CIA regularly sends armed drones to fire missiles at Al Qaeda and other militant suspects in the tribal areas of northwest Pakistan. The CIA also reportedly operated a stealth drone aircraft, known as the RQ 170 Sentinel, before and during the May 2 raid on Bin Laden's compound. Pakistani officials were alarmed because unlike most drones, the Sentinel is designed to evade radar and other surveillance systems, and can be used as a spy plane. It was unclear whether Pakistan intended to take dramatic steps to curtail the drone program. Drone attacks have increased substantially during the Obama administration, and serve as one of the main U.S. tools for fighting Al Qaeda and its allies.