Pakistani officials say a roadside bomb blast near a Shi'ite religious procession has killed at least seven people, including three children.

Authorities say 30 people were wounded in the attack Saturday in the northwestern city of Dera Ismail Khan.

The Pakistani Taliban often carries out such attacks.

Saturday's attack came as minority Shi'ites observed the holy day of Ashura, which commemorates the seventh-century death of Imam Hussein, grandson of the Prophet Muhammad.

Ashura is the tenth day of the Muslim holy month of Muharram, the first month of the Islamic calendar. Sunni extremists have targeted Shi'ites in the past during Muharram, especially on Ashura.

Authorities have tightened security across Pakistan to guard against possible attacks on Shi'ite gatherings during Muharram. Pakistan has temporarily suspended mobile phone service in major cities to prevent bombings, which are often triggered by cell phones