text:  Oman says a shooting at a Shia prayer hall killed at least eight people last night. NPR's Aya Batrawi reports on the rare attack in the Gulf Arab State. Oman's state-owned media say the attack targeted worshippers at a Shia prayer hall in the capital, Muscat, Monday night during the annual Ashura commemoration. In addition to those killed, dozens were wounded, many of them migrant workers from Pakistan.