A school in Pakistan's Peshawar city welcomed students with tightened security on Monday, less than a month after the Taliban slaughtered more than 140 of its peers in one of the deadliest terrorist attacks the country has seen.

Helicopters patrolled the skies and children clutched their parents' hands as they made their way to the Army Public School, with newly installed barbed wire around its walls, to attend a Monday ceremony marking its reopening since the Dec. 16 massacre that left 152 people dead, the Associated Press reported.

Prayers were read from the Quran and pamphlets were passed around to parents and children with information on dealing with the psychological trauma of tragedies like the one at the Peshawar school.

For Abid Ali Shah, he is still reeling from the loss of his wife, a teacher at the school who was killed by the Taliban.

"A hollowness in my life is getting greater. I am missing my wife," Shah told the AP. "Everything is ruined here. Everything."

His two sons attend the school and survived the attack. There are nights when both boys wake up crying for their mother.

"Those who have done all this to all of us cannot be called humans," Sitwat Ali Shah told the AP.

Pakistan has stepped up military operations against the Islamist extremist group since the attack. Several military raids conducted in the country's tribal regions near the border with Afghanistan have killed dozens of Taliban members. The man believed to be the mastermind behind the massacre, Saddam Jan, was also killed.

Despite the crackdown and beefed up security at Pakistan schools, such as installed metal detectors, grieving parents doubt the government is doing enough. Seven paramilitary soldiers were killed Monday by armed militants in an attack in the Baluchistan province.

"We all are scared after this incident," Aurangzeb Khan, who lost one of his sons, told the AP. "I am not satisfied about what they are claiming or what they are doing for security and safety of the children."

Classes will officially resume Tuesday.