Geo News reported at least 27 people died in the violence Wednesday in the garrison city of Rawalpindi, the port city of Karachi and Quetta, capital of Balochistan province.
The worst hit was Rawalpindi where at least 20 people died and another 47 were injured in a suicide bomb attack during a Moharram procession near a Shiite Imambargah (assembly place) in the city's Dhok Sayidan area, Geo News said, quoting police.
"So far we have received credible reports that 20 people have been killed and 47 injured in the suicide blast," a senior police official said.
Hours earlier, there were two near simultaneous blasts at a similar procession near another Imambargah in Karachi, in which two people died and 16 more were injured, the report said, quoting authorities. Those attacks also were believed to have been carried out by suicide bombers, the report said, quoting eyewitnesses.
Also on Wednesday in Quetta, an explosive device planted on a motorcycle went off in the city's Shahbaz Town, killing at least five people including three security personnel, Geo News said quoting a police official.
The report said a security forces' vehicle appeared to be the target of the attack.
The BBC reported no group had yet claimed responsibility for the attacks, although attacks on minority Shiite Muslims have gone up in recent months. Pakistan is a Sunni Muslim majority country.