What motivates suicide bombers to claim their own lives and wreak havoc and destruction? One family, whose son ended his own life in a suicide bomb attack against Iraqi security forces last year, got the answer to this question after he sent them a farewell note before he launched his suicide bomb attack.

In his letter, Alaa Abd al-Akeedi asked his family for forgiveness for what he was about to do, according to Reuters. He told them not to mourn him because there's something better waiting for him in the afterlife.

"Don't be sad and don't wear the black clothes. I asked to get married and you did not marry me off. So, by God, I will marry the 72 virgins in paradise," Al-Akeedi wrote.

Al-Akeedi was just one of many young recruits of ISIS in the past two and a half years. His letter, which was addressed to his parents' home in western Mosul, was written on an ISIS form marked "Soldiers' Department, Martyrs' Brigade."

His relative said Al-Akeedi's father was deeply worried after his son joined ISIS. Al-Akeedi already told his father during his last trip home that he would carry out a suicide attack in Baiji, an oil refinery town south of Mosul. "He told his father, 'I am going to seek martyrdom,'" said the relative, who chose to remain anonymous.

It was only a few months after his death that the family learned he had succeeded. Al-Akeedi was only 15 or 16 years old.

Meanwhile, Iraqi forces arrested early Tuesday a girl believed to be an ISIS suicide bomber before she could carry out her mission to attack a girls school in the liberated area of eastern Mosul, Iraq, Iraqi News reported.

The girl, who wore an explosive belt, was arrested while on her way to blow herself up inside a girls-only school in Wahda district.

On Monday, Iraqi security forces killed two ISIS suicide bombers near al-Salam Hospital, south of Mosul, a police officer in Nineveh Police Command said in a statement.

The two suicide bombers were shot dead by security forces before they could sneak into the hospital, the police statement said.

"Mosul residents informed the police forces [of] the suicide bombers' movements," it added.