The twin explosions occurred in a market in Kurram tribal region when people were buying food to break their Ramadan fast, said a police official.
The blasts left 20 of the 100 injured in a critical condition apart from the casualties, said officials at the Governor House in Peshawar.
The first blast occurred in the Main Parachinar Bazaar in Kurram Agency. It was planted on a motorbike. Four minutes later, the second blast took place on the main School road, authorities said.
Sources said that both explosions appeared to be suicide attacks, but there was no immediate official confirmation about the nature of the blasts.