Five small bombs exploded outside theaters in Lahore, Pakistan's second-largest city, hours after Vice President-elect Joseph R. Biden Jr. arrived here in the capital to meet the country's military and civilian leaders. No one was killed, and only a handful of people were wounded. But the blasts set off a panic, with ambulances and crowds going to the scene, and they served as a reminder of the problems that many analysts believe could make Pakistan one of the toughest foreign policy challenges for Mr. Biden and President-elect Barack Obama. All the bombs appeared to be small explosives that could have done far greater damage had they been more powerful, according to accounts provided by authorities to the Pakistani news media. Police officers searched for other hidden bombs and rushed to guard theaters in Lahore, the cultural hub of Pakistan. There were no immediate claims of responsibility, though one suspect was arrested. The governor of Punjab Province, Salman Taseer, suggested that "anti-Pakistani elements" were to blame. It was not clear why anyone would set off so many low-power bombs in busy areas, unless they were intended only for intimidation. There was speculation that the blasts were a continuation of low-intensity bombings in Lahore last October that struck juice shops known as "dating points," with enclosed booths for young couples to cuddle. One person was killed and several wounded in those attacks. An unknown group claimed responsibility and warned of more attacks against "centers of immorality" in the city. Bombs and other terrorist attacks have soared in Pakistan as thousands of Taliban militants have come to dominate the country's tribal areas. At the same time, Pakistan's eastern border with India is now the most tense it has been in years, after the November attacks in Mumbai, which left more than 160 people dead and drastically worsened relations between the nuclear-armed countries. During a meeting here on Friday with the Pakistani president, Asif Ali Zardari, Mr. Biden discussed the Mumbai attacks, according to a senior Pakistani government official, who spoke on the condition of anonymity according to diplomatic protocol. Mr. Biden talked in depth about the long-term relationship between the United States and Pakistan and how the challenges of Islamic militancy in Pakistan and Afghanistan were closely linked, the official said. Mr. Biden, the Pakistani official said, spoke about how progress in Afghanistan required that the problem of Islamic militancy in Pakistan also be addressed. Mr. Biden's "focus was more on Afghanistan, how to stabilize it and how to defeat the Taliban and Al Qaeda," the official said. He also said Mr. Biden had not only met with Gen. Ashfaq Parvez Kayani, chief of the Pakistani Army, but also took the unusual step of meeting with Lt. Gen. Ahmed Shuja Pasha, the newly appointed leader of the country's main spy agency, the Directorate for Inter-Services Intelligence, or the ISI. An aide to Mr. Biden declined to comment on the meetings, except to say that the vice president-elect emphasized to the Pakistani officials that he was not making any commitments on the part of the incoming administration, and that Mr. Biden was mainly in a "listening mode" during the sessions. Pakistan's civilian government is new and shaky, and much real power has historically rested with military commanders and top-ranking spymasters who have had a history of militant sympathies. Pakistani leaders contend that those militant loyalties are now in decline, but some American officials are skeptical. Officially, Mr. Biden is traveling in a fact-finding capacity as a senator, a job he will leave shortly to be sworn in with Mr. Obama on Jan. 20. But among Pakistani officials the trip was widely viewed as the first visit by the Obama administration. Mr. Biden has been chairman of the Senate Foreign Relations Committee, and he is expected to vie for influence on foreign policy with Hillary Rodham Clinton, the secretary of state-designate. The integrity and allegiance of Pakistani security forces are a critical focus for Mr. Biden. He sponsored legislation that would greatly expand nonmilitary aid to Pakistan for schools, hospitals and other programs, but it could also curtail arms sales and billions of dollars in military aid " unless Pakistani security forces demonstrate a serious commitment to action against militants. As leaders in Islamabad continued to grapple with mounting evidence that Pakistani militants had carried out the attacks in Mumbai, and as American officials pressured Pakistan to be more forthcoming, the prime minister, Yousaf Raza Gilani, suggested on Friday that the country had taken a step toward cooperating with India. Mr. Gilani told reporters that the ISI had provided "feedback" to the Indian government on a 52-page dossier of evidence that he said India had shared with the Central Intelligence Agency, and which was then given to the Pakistanis.