The death toll from twin blasts that tore through a crowded market on Friday in Pakistan's northwestern tribal belt has risen to 37, officials said.

Both blasts came during rush hour in Parachinar on the last Friday of Ramadan, Islam's holiest month, wounding more than 150 people, senior official Basir Khan Wazir told AFP.

"The death toll has now risen to 37, the number of injured people is more than 150," he said.