The explosion took place near a park when the mourning procession was returning from Shershah-Jo-Per to Quetta Road in Lashari Muhalla of Jacobabad on Friday, reported Dawn online.
The dead and the injured were taken to the Civil Hospital and the Jacobabad Institute of Medical Sciences, where condition of some of the injured was stated to be critical.
Following the blast, a group of angry protestors stormed the office of the Deputy Superintendent of Police accusing the law enforcement agencies of providing inadequate security to the procession.
No group has claimed responsibility for the attack yet.
Earlier, at least 10 people were killed on Thursday, when a suicide bomber exploded outside a Shia mosque in Bolan area of Balochistan province.
The attack was the second deadliest bombing on a Shia congregation after 61 people were killed and at least another 60 injured in a bomb explosion in an Imambargah in upper Sindh district of Shikarpur on January 30, 2015.
Security personnel cordoned off the area, while a search and rescue operation was carried out.
Meanwhile, Prime Minister Nawaz Sharif and President Mamnoon Hussain condemned the blast and directed hospital authorities to provide best possible medical treatment to the injured.
Sectarian violence has claimed thousands of lives in the country over the past decade.
Moreover, cell phone services have also been suspended in major cities, including Karachi, as a security measure during the observance of Muharram.
The gatherings and processions during Muharram mark Hazrat Hussein's martyrdom in the Battle of Karbala, Iraq, in 680 AD.
OneIndia News (With inputs from agency)