The radical militant group Boko Haram has already used four times as many child suicide bombers in northeast Nigeria this year than it did in 2016, the United Nations Children’s Fund reported Tuesday.

Eighty-three children have been used as “human bombs” since the start of 2017. Fifty-five were girls, and 27 were boys, UNICEF said. In once instance, a baby was also strapped to a girl.

WATCH: A rare glimpse into the brutality of life under Boko Haram

The number of children has been increasing since the militant group first began using children as suicide bombers. In 2014, four girls were used to detonate explosives. In 2015, 21 girls were used and in 2016, 19 children were used – 15 girls and 4 boys.

Militants spot girls in markets and then drag them from their beds during nighttime raids. In some cases, parents are killed during the process.

“The use of children, especially girls, as human bombs, has now become one of the most defining and alarming features of the conflict in northeastern Nigeria,” said Milen Kidane, UNICEF’s chief of child protection.

The Boko Haram insurgency is fueled largely through systematic abduction of children, according to UNICEF. Militants spot girls in markets and then drag them from their beds during nighttime raids. In some cases, parents are killed during the process.

Many captives are then forced into early marriage and sexual slavery. Boys are typically forced to become child soldiers, according to UNICEF.

UNICEF speculates that Boko Haram uses children because they can be easily manipulated, and enter public spaces with very little suspicion.

Most children do not realize they are carrying explosives, and those that do have been brainwashed to carry out the attack, according to UNICEF.

UNICEF assumes that young girls are used more often because they are seen as the least suspicious.

“In these mostly Muslim communities, their attire, their dress code, its very easy to hide some of the bombs within their clothes,” Kidane said. “So it’s very convenient, in that sense, to use a girl child.”

Because of the increased use of children as “human bombs,” people are becoming fearful of the young, which has a devastating impact on children who are returning from abduction.

Additionally, young girls who return after being sexually abused often face discrimination, especially if they are pregnant.

Because of the increased use of children as “human bombs,” people are becoming fearful of the young, which has a devastating impact on children who are returning from abduction.

In an effort to re-acclimate children who have escaped and returned home, UNICEF is hosting interventions and reconciliation activities with entire communities, not just the children in northeast Nigeria, led by respected community and religious leaders, and influential women.

“We try to bring the communities together, so that they understand, in fact, that these children are victims whether they spent time with Boko Haram or not,” Kidane said. “We’re trying to bring everyone together, working together and trying to heal as a collective rather than to further separate the victims versus the perpetrators.”

READ MORE: What Is Boko Haram?

As a result of its offensive, the terrorist group has displaced over 2.3 million people since May 2013, making it one of the fastest growing displacement crises in Africa. The number of displaced children increased 60 percent over the last year, from 800,000 to 1.3 million children.

More than 670,000 of those children are no longer in school. More than 1,500 schools have closed after being attacked, looted, set on fire or used as shelter by displaced people.

UNICEF speculates that decades of extreme poverty in the region and inadequate education may have attributed to high number of recruits, who are offered food, power and the promise of spiritual rewards.

“Sometimes they’re told, ‘If you do this, you’ll get to heaven,’ or, ‘If you do this, it’ll help your family members.’ They’re told whatever it is that they need to hear in order to be convinced to do this,” Kidane said.

Nigeria is also one of four countries experiencing famine, leaving up to 450,000 children at risk of severe malnutrition this year, according to a UNICEF statement.