A leading human rights group says Pakistan's Shi'ite Muslims are living in a state of siege, after a string of bombings across the country killed 115 people and wounded nearly 250, in one of the nation's deadliest days in years.

Ali Dayan Hasan, the Pakistan director of Human Rights Watch, warned Friday that sectarian violence will likely rise, a day after 82 people were killed in Quetta in suicide bomb blasts in a billiards hall frequented by Shi'ites.

He said more than 400 Shi'ites were killed last year and “if yesterday's attack is any indication, it's just going to get worse.”

The billiards hall attacks came just hours after a deadly bomb blast at the Quetta market.

The outlawed militant Sunni group Lashkar-e-Jhangvi contacted local media to claim responsibility.

Shi'ites make up about 20 percent of Pakistan's mostly Sunni Muslim population of 160 million people.

Elsewhere in Pakistan Thursday, at least 21 people were killed and more than 70 wounded in a bombing in the city of Mingora, where a crowd had gathered to hear a speech by a religious leader. Mingora is the largest city in northwestern Pakistan's Swat province.

No one has claimed responsibility for that attack.