Authorities say the attack happened Saturday in the city of Dera Ismail Khan, located near the South Waziristan tribal region.
Pakistan has temporarily suspended mobile phone service in major cities to prevent such bombings, which are often triggered by cellular phones.
Authorities have tightened security across the country amid intelligence reports of possible attacks on Shi'ite gatherings during the holy month of Muharram.
Sunni Islamists have targeted Shi'ites in the past during Muharram, especially Ashoura, when Shi'ites commemorate the seventh century death of Iman Hussein, Muhammad's grandson. Ashoura falls on Sunday this year. VoA.