Actually it was a jihad/martyrdom attack perpetrated by Sunnis. Will the Islamophobia never end? "Shia Muslims targeted in Pakistan's suicide attack: police," from [1] Xinhua, March 5 (thanks to Twostellas):

A suicide bomber on foot killed at least five people, including three women, in Pakistan's northwest, a senior police officer said Friday.

The bomber exploded his bomb near a convoy of buses, carrying Shia Muslims, in Hangu district, destroying three vehicles, police officer Islam-ud-Din said.

Commissioner Khalid Khan earlier said that ten people were killed in the attack....

Police described the attack as sectarian as Shia Muslims were targeted. Hangu district has seen a series of sectarian attacks in the past but the area had been calm in recent months....