Islamabad , Pakistan ( CNN ) Pakistani authorities have arrested a suspect in the December 16 attack on a public school in Peshawar that left more than 140 people dead , most of them children . Taj Muhammad , also known as Rizwan , is accused of commanding one of the Taliban units that laid siege to the Army Public School . The military says he has confessed to other attacks in the same area . Taliban militants ambushed the school , explosives strapped to their bodies , and burst into an auditorium filled with students taking exams . They sprayed bullets rapidly , killing 145 people . Of those , 132 were children , authorities said . The terror group had warned Muslims to avoid places with military ties , saying it carried out the attack to avenge the deaths of children allegedly killed by the nation 's army strikes in tribal areas . The army school is home to about 1,100 students and staff , most of them sons and daughters of army personnel from around Peshawar . CNN 's Sophia Saifi reported from Islamabad , and Mariano Castillo reported from Atlanta .
Mariano Castillo , also known as the Army Public School , has been arrested , Atlanta military says . He is a suspect in the December 16 school massacre that killed 132 in Peshawar .