NEW : Intelligence warned of possible Lahore attack . Militants said to be from Waziristan tribal region . 98 killed in Pakistan's worst terror strike since 2008. Attackers targeted houses of worship for persecuted sect .
NEW : Intelligence warned of possible Lahore attack . Militants said to be from Waziristan tribal region . 98 dead , 110 wounded in Friday 's attacks . Attackers targeted houses of worship for persecuted sect .