Explosions in two Pakistani cities killed 32 people and injured more than 100, police and hospital officials said. A bomb in Quetta, the capital of the eastern province of Balochistan, killed 11 people and injured more than 40, police officer Zubair Mehmood said.
A local militant group claimed responsibility.
Another 21 were killed and more than 60 injured in a blast where people had gathered to hear a religious leader speak in Mingora, the largest city in the northwestern province of Swat, police and officials at the Saidu Sharif hospital said. "The death toll may rise as some of the injured are in critical condition and we are receiving more and more injured people," said Dr Niaz Mohammad.
Police said the Swat blast was caused by an exploding gas cylinder but many of those present said they doubted that.
"There was no cylinder where the blast took place. We all know that gas cylinder does not kill so many people," said one of the injured, Mohambar Khan. Another injured man also said no gas cylinders were nearby.
If the blast was a bomb, the death toll would have been the highest on one day in Swat for more than two years. The mountainous region, formerly a tourist destination, has been administered by the Pakistani army since their 2009 offensive drove out Taliban militants who had taken control.
But the Taliban retain their ability to mount attacks in Swat and shot schoolgirl campaigner Malala Yousufzai in Mingora last October. The bomb in a market in Quetta targeted a police patrol and mostly killed sellers of vegetable and second-hand clothes, officer Mehmood said.
Three police officers nearby were injured and a child was among the dead, he said.
The United Baloch Army claimed responsibility for the blast.
The group is one of several who are fighting for independence for Balochistan, an arid and impoverished region with substantial gas, copper and gold reserves. It constitutes just under half of Pakistan's territory and is home to about 8 million of the country's population of 180 million.
Human rights groups say hundreds of bodies have been recovered in the region since 2011. Many have broken limbs, cigarette burns or other signs of torture. Local activists blame the security services.
The state denies the accusations and says that insurgents sometimes put on military uniforms before kidnapping people. Sectarian attacks are also on the rise, and militant groups frequently bomb or shoot Shia passengers on buses travelling to neighbouring Iran.