RAWALPINDI, Pakistan (AP) — A suicide bomber killed 35 people outside a bank near Pakistan's capital Monday, as the U.N. said spreading violence has forced it to start pulling out some expatriate staff and suspend long-term development work in areas along the Afghan border.

Hours after the first blast, another suicide bomber struck in the eastern city of Lahore, exploding a car at a police checkpoint as officers went to search it. At least seven policemen were injured and two were in critical condition, officials said.

"By putting their lives in danger, our men have saved the city from enormous sabotage," Lahore Police Chief Pervaiz Rathor told reporters at the scene.

Checkpoints, where cars are forced to drive slowly past police officers looking inside, have become common sights across Pakistan amid a surge in violence that has left at least 300 people dead over the past month. The violence has grown bloodier since the government launched an anti-Taliban offensive in mid-October.

Several U.N. personnel have been among those killed in the violence, and the world body's decision to curtail development work could imperil Western goals of reducing extremism by improving Pakistan's economy.

The first attack Monday came in Rawalpindi, a garrison city just a few miles (kilometers) from Islamabad. It occurred as many people waited outside the National Bank on a pay day to collect salaries.

The bank is close to the army's headquarters, and a majority of the people waiting in line were from the military, said Mohammad Mushtaq, a soldier who was wounded. Militants raided the headquarters last month, triggering a 22-hour standoff that left 23 people dead.

"I was sitting on the pavement outside to wait for my turn," said Mushtaq, who suffered a head injury. "The bomb went off with a big bang. We all ran. I saw blood and body parts everywhere."

Four soldiers were killed in the attack, and nine were wounded, said the army's chief spokesman, Maj. Gen. Athar Abbas. In total, 35 people were killed, said Information Minister Qamar Zaman Kaira. Several dozen others were wounded.

No group claimed responsibility for the bombing, but that is not unusual in attacks that kill many civilians.

Pakistan's president, prime minister and other top officials condemned the blast but vowed to continue the offensive in South Waziristan, an impoverished and underdeveloped tribal region next to Afghanistan where al-Qaida is believed to have hide-outs.

Abbas said the army had captured the town of Kaniguram, one of the Taliban's bases, and killed 12 more militants in the past 24 hours of the offensive, which began in mid-October. The U.S. supports the operation because it believes South Waziristan is a safe haven for Islamist extremists involved in attacks on Western troops in Afghanistan.

The top U.S. and NATO commander in Afghanistan, Gen. Stanley McChrystal, met with Pakistani army chief Gen. Ashfaq Parvez Kayani on Monday at the army headquarters in Rawalpindi. The U.S. Embassy declined to say if he was there at the time of the attack.

Washington has stepped up its efforts to use development aid in a broader battle against spreading militancy. The U.S. government recently approved $7.5 billion in aid over five years to improve Pakistan's economy, education and other nonmilitary sectors.

But the U.N. decision to suspend long-term development work in Pakistan's tribal areas and its North West Frontier Province could frustrate Washington's goals.

The U.N. made its decision after losing 11 of its personnel in attacks in Pakistan this year, including last month's bombing of the World Food Program's office in Islamabad that killed five people.

The world body will reduce the level of international staff in the country and confine its work to emergency, humanitarian relief, and security operations, and "any other essential operations as advised by the secretary-general," the organization said in a statement.

The U.N. has been deeply involved in helping Pakistan deal with refugee crises resulting from army offensives against militants in the northwest.

U.N. spokeswoman Amena Kamaal told The Associated Press that the organization is still determining which programs will be suspended and how many staffers will be withdrawn from the country. She said "long-term development" applied to programs with a five-year or longer timeframe. The staff that remain in the country will be assigned additional security, she said.

"We have had 11 of our colleagues killed because of the security situation," Kamaal said. "All of the decisions are being made in light of that."

The U.N. has deemed 12 other countries or parts of countries so dangerous that it has suspended long-term development work, but that does not include Afghanistan, said Ian Miller, a U.N. official in Islamabad.

Foreign Ministry spokesman Abdul Basit said Pakistan understood the U.N.'s reasoning, but that he hoped the organization would resume its development work after the military completes its operation in South Waziristan.

Pakistan's shaky, U.S.-allied government also came under pressure Monday when a faction of the ruling coalition said it would oppose a measure being debated by Parliament that grants President Asif Ali Zardari and other lawmakers amnesty from corruption charges.

Such a rift within the ruling coalition could lead to distractions just as the U.S. wants Pakistan to focus on fighting militants.

Zardari denies the corruption allegations and has already spent years in prison fighting them.