A suicide bomber has killed at least 16 people during Friday prayers at a Pakistan mosque, a regional official says.
"The suicide bomber was in crowded mosque, he shouted 'Allahu Akbar', and then there was a huge blast," Mohmand Agency deputy administrator Naveed Akbar said.
Mohmand Agency is a tribal district in northern Pakistan.
Shaukat Khan, another official in the northwestern FATA region, said at least 24 people had been wounded.
"Many people were gathered inside the mosque where a suicide bomber blew himself up," he said.
Pakistan's frontier regions, which are deeply conservative and hard to access due to rough terrain, have long been the sanctuary of fighters from al Qaeda, the Taliban and other Islamist groups.