"The secretary-general is appalled by the escalating terrorist violence in Pakistan,” a statement issued by Ban’s spokesperson said on Sunday.
“He condemns in particular the continued violent targeting of religious minorities,” the statement added.
On Sunday, at least 19 people were killed when a bomb ripped through a convoy of three buses carrying Shia pilgrims in the Mastung district, south of Quetta in Balochistan Province.
According to reports, a number of women and children were among the victims. A senior government official in Quetta said the buses were carrying some 180 Shia pilgrims, who were on their way to Iran.
Attacks against Shia Muslims in different parts of Pakistan have escalated in recent months. Since the beginning of 2012, hundreds of Shias have been killed in the country.
Last month, many Shia Muslims were killed in several attacks targeting processions held to commemorate the martyrdom of the third Shia Imam, Imam Hussein (PBUH).
Pakistani Shia leaders have called on Islamabad to form a judicial commission to investigate the bloodshed.
The UN chief also slammed the killing of 23 Pakistani paramilitary troops who had been kidnapped earlier this week in northwestern Pakistan by the Tehrik-i-Taliban Pakistan (TTP) militants.
"These cruel acts of violence cannot be justified by any cause or grievance… These perpetrators should be brought to justice,” the statement added.
On December 27, nearly 200 heavily-armed TTP militants stormed three government security checkpoints on the outskirts of Peshawar and kidnapped 23 troops from the tribal police force. Two officers were killed in gun battles with the militants.
"We found 21 bullet riddled bodies of security personnel a short while ago in an uninhabited area," local government official Naveed Akbar said on Sunday.
Source: Press TV