A blast has killed at least 43 people in the southwestern city of Quetta at a Shiite procession calling for solidarity with Palestinians.
It is thought that another 78 people were wounded, with several in a critical condition.
Protesters dragged wounded people into private cars as burning motorcycles sent clouds of black smoke billowing through the streets. The bodies of the dead and injured lay strewn across the road.
Earlier, a suicide attack on a mosque belonging to the minority Ahmadi sect killed at least one person and hurt several others in the northwest Pakistani town of Mardan.
A triple suicide attack on Wednesday night killed 35 people at a Shiite ceremony in the eastern city of Lahore.
Wednesday's attack in Lahore, and a host of other assaults on religious minorities, was claimed by the hardline Sunni Pakistani Taliban, which is seeking to overthrow a Western-backed government, shaken most recently by flooding that has caused massive displacement, suffering and economic damage.